Hi Betty,
more info! what software do you use, what computer, what was the old control surface, how many channels do you need, what features are you looking for...
you can read some things here at tweakhead:
http://www.tweakheadz.com/control_surfaces.htm
to get an idea
I like to follow a manufactures suggestions, so if MOTU wants to see a particular control surface I'd start there. Mackie is solid stuff, but there are so many other companies that make good gear now.