I haven't even been seeking out free resources, but keep stumbling upon things that I think are worth sharing with the world.
A few free data collection sheets: http://www.autismbehaviorbox.com/tools/?goback=%2Egde_4258469_member_273870027#%21
The Reinforcer Assessment is a crucial piece to any ABA programming that all too often is either forgetten or breezed over. Never under estimate the power of a good reinforcer!
Leanne Page, MEd, BCBA