This weekend you can get 8' intex pools for $25 at Big Lots and other discounters. These are not supplied with the cheap junk pumps, so it is just the pool. You can add a decent pump on your oun $. It looks like they are plumbed for pumps. I bought 4 for my project. Hard to go wrong.
This is http://www.intexcorp.com/easy8x30.htm model 56970/E