I go to the kids section of office supplies in KMart. The off-white cheap tablets have very good paper for paper piecing. I try to get the 81/2 by 11" tablets because they fit in the copier. They tear away much easier than notebook paper of copy paper and are even cheaper. Be careful when you iron each peice because the ink can transfer onto your ironing board cover.
I use long serger tweasers to pull of the paper in hard to get at places. It is also good to "snap" the piece by quickly giving it a little stretch. this seems to get the paper to pop off!