Watch the Dickey Betts online guitar lesson by Jeff McErlain from Kings of Tone
When I look for a good overdrive pedal I look for one that reacts like an amp. There are A LOT of overdrive pedals out there and many of them are excellent. I recommend going to a good music store and checking some out. I highly suggest you bring your guitar and try to play the pedal through your amp or as close as you can get. A pedal that sounds great through a Fender amp may not work so well through Vox. It's all about how the pedal reacts with the amp's circuit. That's why I have about 6 OD pedals!