Ok, a NTC Factory kit will be a nice choice. For an engine, how about something along the lines of Novamega?
http://www.mytsn.com/products/prodlist.asp?prcid=20 That link is for a bunch of .12 motors from Novamega. You'll also need a starterbox, so...
http://www2.towerhobbies.com/cgi-bin...?&I=LXCLZ9&P=M That will also need a battery/charger.
And for the spoilers...yes, they do make a difference, they affect the handling tremendously at high speeds.