The Global Right Flyer 60H is a pretty nice trainer. It sells for about $140.
http://www.hobbypeople.net/gallery/125814.asp
I had one of these for about 2 years. It survived a lot of abuse before I finally killed it.
It has a 71 inch wind span, with semi-symmetrical airfoil. It does not have a lot of dihedral, so it doesn't have as much "self recovery" tendency as some trainers. With buddy boxes, and good instructors, I'm not sure that's a negative. One of my instructors (Bill) was a pattern competitor. He could make this plane do a lot, and it looked pretty good doing it. My aerobatic attempts didn't look as good as his, but I feel like I learned a lot using this plane. Bill often told me, "If you give it xxx control input to start a maneuver, you typically owe it opposite input at the end." He doesn't like depending on the plane level to itself.