Yo, Baltimore here. And, Welcome to RCT!
I go to the Track in Gaithersburg. 10th scale indoor offroad (dirt) and Mini Zs - fully stocked shop. I will also be going to 180 Raceway soon to start my on-road racing adventure.
@Smilinbri , @Jpslash667 , and @johnnydmd might know more places. (and...