I just finished my first 6 week "540 silver can series". My best advice (if it's in your budget) is to get a new car and build it yourself...pay extremely close attention to the manual. The build experience is really valuable when you have to fix something.

I ran the Tamiya TA05 IFS-"R", which is a great car. Wanted more precision and accurate tunability, so just sold it and am putting two used xray 007 chassis together. You don't need to get the "R" version, BTW. If you're just using it as a stepping-stone car, get the regular TA05 or TA05 IFS.

Don't be afraid to ask questions at your track. Pay really close attention to the consistently fast drivers. If your track is anything like mine, there will be no shortage of valuable advice!

Oh yeah...have fun!