I go through a lot of zippers...I mean A LOT. Several years ago, I started buying my zippers in bulk on eBay from ZipperStop. They have never done me wrong...fast shipping, great customer service, and great prices.
There are a lot of zippers available in their eBay store. But for most sewing projects, I use Nylon Coil #3 zippers (close-end). I prefer YKK to Talon only because I think YKK are easier to open.
I typically buy the assorted 9" and 10" zippers on eBay. And the other ones I buy from the actual ZipperStop website. The most common length I buy is 12" - for the bargain basement price of $32 for 100 - yes...that's 32 cents each. I always buy the assorted colors - and they arrive looking like a bouquet of flowers. In fact, it's difficult for me to take them out of the rubber band!
Here's my latest project made from my ZipperStop zippers. It's my version of the Hip Klip!
Have fun sewing with zippers!