AC Power cords, which components 1st...?

I've been lying in the background with regard to upgrading power cords and I'm now thinking that I might give it a try. I fully subscribe to the laws of diminishing returns with the exponential (if not worse) price curves of these products. Therefore, I'd be looking in the $50 - $250 dollar price range. I don't need long cables (3 - 4 ft should work) and that may help the price point. Pre-owned is fine with me as well.
Given that, which components first? power amps, pre-amp, source...? and, any thought on power cord given my predisposition?
Aloia power amps, Casanova pre/pro. Capitole MKII (soon, I hope).
If you are using a power conditioner with a removeable cord, then start there. That place affects the power for all the components in the system. I would do the CD player or DAC next; then the power amp. If you use a sub, then a better cord will usually tighten the bass.
The amp should be the first to get the upgrade.
According to David Blair at Custom Power Cord, the order of upgrading should be: 1) CD player 2) preamp 3) power amp. His power cords have won T.A.S. Golden Ear Award (Top Gun)! I highly recommend the Top Gun (there are three versions, depending upon the current draw of the component).` The entry level Model 11 is also an excellent choice if your budget won't let you spring for a Top Gun set up. Happy Tunes!
I agree with Sugarbrie ... at least as far as starting with the CD player/transport first, before the preamp/amp/integrated. The old saying about "garbage in ... garbage out" is certainly true in audio as well. If you send a dirty signal to the amp, you will just amplify the dirty signal. So, at least start with the CD player, and then work towards the end of the chain.
The same rule applies to purchasing components, you buy the best source component that you can afford. Then you buy the best amp you can afford. And last, you buy the best speakers you can afford. William Z. Johnson (truly a pioneer among audio manufacturers as the head of Audio Research Corporation ... and a most credible audiophile!) long before ARC had a source component to offer, and before the days of CD, made that astute observation. He said that you should start with the best cartridge/tonearm/turntable you can afford, and then buy the best preamp, and so on. That statement in the context of things, was a very honest approach to starting someone on the right foot in audio!
The only reason I hesitate about making the power conditioner the first component to replace the power cord is because it should be cleaning up the line voltage within itself. But, I won't argue that point until I've tried it myself ... I have tried the other and know!
Between the DAC and Transport which would be first.
The Cheapskate answers:
Don't fret about it. Keep a look on audiogoN and buy one each of cables as they come up for less than $70 each including shipping. Play around with each cord as they arrive. Cords are very system specific. With the law of diminishing returns, if you haven't already jumped into buying power cords, then your system isn't ultra expensive class A already, and the benefits to be had from power cords at the upper range of your price guidelines aren't likely to provide significantly superior sonic results.
So get a variety of sub-$70 cords. Switch them around. See what sounds best and works best for you. This way you can do your entire system for close to what you have budgeted for one expensive cord. Let your own ears decide.
I disagree with Brtritch. One need not have a class A system in order to appreciate the addition of a top flight pc. Of course, placing a $1000 cable on a $500 component doesn't make much sense either. Having said that, I have heard expensive pc's make profound improvements in modest systems.

My recommendation would be to go to a service oriented dealer and audition some pc's. Try the cables on a couple different components. Then decide if the pricier cables seem to be worth it. Keep in mind that pc are very component dependent. Next, borrow the pc's for an in-home audition. My personal experience suggests starting with the amplifier first but as long as you have the cables at home, try them on different components. Also, keep in mind that high capacitance pc's can cause problems in a system. I've had some that created power supply transformer hum and system noise that was audible from the listening position.

For what it's worth, the $340 Shunyata Sidewinder Gold pc on my monoblocks made the single biggest improvement in my $30,000 of any upgrade I've made in the last couple of years.
To answer one of questions about where do you first put a powercord on the Dac or Transport in the majority of systems the transport has a much larger effect than the Dac.
But as with everything in Audio there is no absolute. We have found a few rare cases where the Dac has a larger effect.

A powercord greatly improves the effects of a line conditioner.

Shunyata Research has just come out with the best Audiophile powercord that I have ever heard under $200 the Diamond Back at a retail price of $150. Having said that let me also state that I am a Shunyata dealer. But I have just finished listening to them for over a week and they are very good. Better than I expected them to be at the price point.

Also, do not be surprised, as have so many Audiophiles' before you, that once you experience the effects of upgraded powercords in your system that suddenly your budget will rise.

Good luck you are in for a surprising experience.
PS.....I say to start with the AC conditioner/regenerator, etc, if there is one, not so much for cleaning up the power, but to be sure your system is getting enough current. Anyway, the conditioner/regenerator will not have to work as hard if it has a good cord connecting it to the wall.
Check out the cables from Virtual Dynamics on Audiogon. $75 for a 6ft cryoed p/c. Just purchased one for myself and it's incredible. Spoke to Rick at VD and he said they are having a big sale to get some product recognition.
I would buy one and experiment. My experience has proven that it's not possible to predict the benifit to a single component within the system. I know from personal history the BMI Whale is a good fit for the Aloia, and I know the power snakes are very strong with the Casanova. Try the new Python, it is a very good cord. I use all NBS Statement but they will push your budget even used.
Definitely put a low-inductance cord directly to the wall outlet for your power amps first. Also, upgrade the outlet to a 15-amp with no steel in it - only brass. IF you want a really low-resistance connection, use the silver-plated Acme audio outlets.
Thanks all...a lot to consider.
When my dedicated 20 amp lines were installed several years ago I installed standard "hospital grade" outlets. That was before this new buzz/hype with regard to the audio grade outlets. Anyone know what the composition is in the hospital outlets?
I have several audio grade outlets but have not a/b compared them (too much hassle). And I don't really put a lot of stock in them but it's such an inexpensive upgrade it doesn't hurt to have them.

What I have discovered though, is that most any cheap or expensive 20 amp outlet will grasp a plug much tighter than a cheap 15 amp outlet.

My system is not a big investment ca. 8M though a good ammount of time has been dedicated to feed it the best in cost /performance in mind and set up and tweaks have really improved the quality of the sound coming out of it.
As part of this process have dedicated lines and also I have changed PC in my source, preamp amp and the results have helped quite a bit. I´m very satisfied with the where the performance of the system has climbed to.
"The old saying about "garbage in ... garbage out" is certainly true in audio as well. If you send a dirty signal to the amp, you will just amplify the dirty signal. So, at least start with the CD player, and then work towards the end of the chain."

This doesn't isn't really clear, as there is no difference if my pre-amp adds 1% distortion or my power amp adds 1% distortion. The source of this folklore is of course the tt manufacturer Linn to help them seel higher priced turntables. When a mechanical device is the source it needs much more attention to setup and quality to retrieve the information available. Today any cd player will retrieve all the info available on disk with minor differences between them. So this isn't the reason to choose where to put a power cord.