It’s crazy difficult to find any bulk (large quantity) supplies of bike tire patches and glue.
Wal-mart carries some cheap, consumer-grade glues, but no rubber cement. (Also, I’m a bit unclear on the difference between rubber cement and the “self-vulcanizing glue” sold with small patch kits.)
Amazon carries practically nothing along this line. (What’s up with them, anyway? Their “long tail” seems to be getting shorter lately.)
You also have to decide whether you want to go with the traditional Rema type patch or the park tools glueless patches (make sure you follow the instructions) or the newer (not well-liked) “slime” options.
Various on-line bike supplies retailers carry modest attempts at bulk patching supplies:
Finally I found what appears to be a much better possibility: make your own patches!! Use cuts from an old tube and use the rubber cement you get from the hardware store. Hexane (art supply store, may be called “Bestine”) is the solvent in rubber cement and is a good cleaner for prepping the patch spot or for cleaning the talc out of the tube you’ll be cutting up for patches.
If you’re nit-picky about the patches being pretty, you can sharpen the end of a steel tube and use it to stamp out nice round sections of rubber from your sacrificial tube.