I use Lionel and Plasticville for my buildings. You can get most of them for under $20.00, and they are easy to paint. I use a LeMax cobbelstone mat for the road and painted matting for the sidewalk. I've also used grey linilium for the road as well. You can get some pretty good deal for cars on e-bay. Lledo ,or Matchbox yesteryear are good bets. Don't ask me about scale comparison. I've bought a lot at flea markets. Check out my photo site, or PM me.
Mike