If you want something simple tp put together check out www.spadflyer.com. I have one with a K&B .45 on it and it performs very well. Cost is $49 plus you need 2 - 2.5 " wheels, a Dubro tail wheel, and a Hayes 8oz tank fits nicely.
One caution - needs a little down trim because the Clark Y airfoil has a lot of lift. Flys better than a Durastick and is very rugged.