Here are some decent 2wd stadium trucks for under $300. They would be very good for a beginner. I picked 3 different RC companies:
http://www3.towerhobbies.com/cgi-bin...H00**&P=ML
http://www3.towerhobbies.com/cgi-bin...XPVD8&P=ML
http://www3.towerhobbies.com/cgi-bin...XPAC9&P=ML
A pretty decent1/8 scale buggy for a beginner:
http://www3.towerhobbies.com/cgi-bin...XRSU8&P=ML
If you have a local hobby store see what manufacturer's parts they carry and go with that vehicle. Having local parts support is a big plus. Of course youcan always order online if you have the time to wait for shipping.