1) does the cd drive matter to the rip? or do i just need to use a good software like EAC or the like to ensure an accurate rip?
EAC will ensure the data you rip matches what was originally on the disc. However, I believe EAC is Windows-only. The only OSX equivalent I know of is called "Max". However, I haven't used it, so I cannot vouch for it. Also, the drive doesn't matter per se, as most recent drives will rip at many multiples of the normal CD speed. However, ripping 3000 discs will put a lot of wear and tear on the drive, so you may want one that you can easily replace if the first one dies. I have a Mac Mini as my primary computer and used it to rip about 1000 discs. However, if the drive died I would have been hard pressed to replace it without bringing it to an Apple retailer for service. On a desktop PC, I could have replaced the drive in 15 minutes for US$20.
2) if i rip on a PC, do i have to use a PC in the future, or can i use a Mac against my external music store if it was created under a PC?
You can rip on a PC and play the songs on a Mac, assuming you rip the songs into a format the Mac understands. AppleLossless and FLAC will both work on a Mac, although iTunes works much better with Applelossless (you can get iTunes to play FLAC, but it's a pain).
3) what sort of redundancy is in order? RAID 1? RAID 5? or just another HD the same as the one i plan on playing from, and simply use it as a backup?
After I ripped our discs, I just copied the files to two other external hard drives. One of them stays at our house and gets updated with new music and the other is stored at my parents house. It took a long time to rip all of those discs. If something terrible should happen (fire, burglary), the off-site drive will let me recover that music. It took some time to copy all of that data to the second drive, but the peace of mind was definitely worth the modest time and cost.
4) which uncompressed file format should i use? AAC or something else?
Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format, AAC generally achieves better sound quality than MP3 at similar bit rates.
If you want lossless, go with AppleLossless or FLAC. My recommendation is AppleLossless. You can easily convert from that to FLAC later if you want to (on a Mac you could use a program called XLD to do so, which is fast and free.)
5)any estimate of how much storage would be required for 3k CDs? or would it be feasible to split my music collection across 2 primary HDs...like A-L, M-Z...which is really asking if playback software can read across multiple drives in one virtual "library"
The simplest way to determine how big of a drive you need is to assume each CD consumes 500 megabytes of space (things originally released on LP will be less, more recent releases will probably be more.) In that case, two CDs equals one gigabyte*. Given the 3000 CDs you're looking to rip, that would mean you would need 1.5 terabytes of storage space. However, using FLAC or AppleLossless would reduce the size of each disc, and therefore mean you could get by with a smaller drive. But given that a two terabyte drive these days is around US$100, there's no reason to skimp, and the extra space will give you room to grow.
5) are rips sensitive to vibrations, power conditioning, etc?
Computers are sensitive to power fluctuations, but using EAC or a similar program will let you ensure the ripped data matches what was on the disc, so you should be OK even if your power isn't perfect.
*To the computer geeks out there, I know a gigabyte isn't 1000 megabytes, but it makes the math simpler for this exercise.