My favs atm de_laguna, de_karachi01, cs_shogun_final and maybe de_plaka. Ok so there are plenty of others but little need to go there . I'll be in for a game if I'm around and can put up with the the pings playing from the other side of the planet.
Looks a little empty. May I suggest trying 66.150.160.135:27015 . They all seem to be great guys & girls that play there plus they do have some great maps in rotation, with the new feature set-up for downloading of maps, so it shouldn't even take a minute to download any of the maps you don't have.