I answered my own question. Based on amazon.com ratings I purchased the Kaplan GMAT 800, 2005-2006 and The Official Guide for GMAT Review, 11th Edition. Apparently there aren't many differences between these and the newest editions.
For a whopping total of $19.35 ($8 of which goes to shipping).
I too wanted to spend as little as possible on studying material when I started but I think OG12 is well worth the $22. I used both OG11 and OG12 and I think at least 30% of the problems in OG12 are new material. It was a good investment
Definitely need OG 11 or 12. The other ones you could probably get away with 2006 editions, though if they correspond to OG problems, that might be off.