Sunlite Bulk Patches on amazon.
100 patches for < $7
These are VERY nice patches. A bit larger than you typically get in the small LBS patch kits...and not bulky. They are thin and patch beautifully. Win-win. Cheap and superior. I'm half way through a box of these that I bought a few years ago. I patch everything with full confidence and have tubes with 3,4,5 patches on them that I trust every bit as much as new.
http://www.amazon.com/SunLite-93007M...7953134&sr=8-1
-Jeremy