I need a recommendation for long(er) cables

I want a well built set of cables with quality terminations around 20-25 feet long.  I do not have a high enough resolution  system to warrant anything expensive.

I need to get my stand mount bookshelf speakers positioned better and I just do not have enough length now.

Buy Canare 4s11 cable by the foot and terminate yourself. Otherwise check out Blue Jeans cable they can provide quality terminated pairs at length desired. 
DH Labs Silversonic, Supra Ply and Zu Cables are my choices and are available on eBay.
Awesome.  I will check these out.
I also like the canare 4s11.  I have an older tube amp and the standard spade terminations on the Blue Jeans canare 4s11 are way too large to fit.  Probably not a problem on a newer amp.
best thing is to run balanced from your balanced pre-amp to your balanced monoblock amps, which are sitting right next to your speakers

is that doable for you?
Try Signal cable, I have purchased upto 70' speakers and balanced cables for rear channels from Frank...excellent build quality and always a great friendly service. 

I've got 3 25' pair of www.signalcable.com in system now. Bought them to hold me over but now I'm thinking of keeping them in system. Fast, quality work, sound good.
I recently purchased some Wireworld Eclipse 7 "mini" (I also have Eclipse 7 "Maxi"). OCC copper with superior (claimed) di-electric insulation. Not the cheapest but very descent wire...
I have a perfect set of cables in that length if interested.
50 feet of Canare 4s11 should cost you ~$75. Can be terminated single or biwire.