Im looking to make a few guns.
I can think of a couple, here you go:
1. the most common one is ebay, you can look at many deals and this is probably one of the easiest ways to get knex. i used thsi way and got 4500 knex for 50 bucks!
2. try the goodwill or salvation army stores. they are bound to have some knex lying around
3. there is this website freecycle.com or something, you can get stuff there
4. garage sales are great too because if you find knex, you can get it really really cheap
i really hope this helps! good luck :)
Ebay.These questions are the new block triggers! =O
Try your local flea market and buy and sell.
You can get knex on ebay and you might be able to find some on freecycel and craigslist