Ralph, welcome to RCU and our addiction, er hobby! Having a local club check out what you've got is a good idea. They will also be one of your best sources for help in finishing the plane, and learning to fly it. You could also take some pictures and post them here, some of us may be able to figure out what you've got.

Assuming you have a typical 40 sized trainer, any engine in the .40-.50 range should do well. If you're on a budget, a bushed .45 size would be a good choice. Thunder Tiger, OS, SuperTigre and others all have engines in this size range.

For a radio, a basic 4 channel will do just fine. JR, Hitec, Airtronics, and Futaba are all good. Check with the local club to see what the instructors are using. This way you'll be sure to have something they can buddy box you with.

Edit: missed a few things.

This thread has links to some great covering videos: http://www.rcuniverse.com/forum/fb.asp?m=4385133 .

To find a club, visit your local hobby shop or try the AMA club locator: http://www.modelaircraft.org/clubsearch.aspx .