There are three shops off of 75 (central) Kawasaki Suzuki between spring creek and parker on the west side, Plano Honda off of Parker across from Target, behind Taco Bell (west side of hwy) and Central Yamaha off of Legacy on east side of hwy (take legacy exit hit the stop light/dead end thingy take a left, drive a little ways and its on your right. central yamaha and plano honda have pretty good selections, suzuki is okay kinda sucks there. There are alot of other shops around but these three are really close togeather.
There is also a Richardsons Motorsports (yamaha) off of 75 too, but i forget the exit.