If you just want CS, you can grab the Steam Cache + CS from GotFrag, here: http://www.gotfrag.com/portal/files/126/
If you want all the Steam games (CS, DOD, TFC etc), you can grab it here: http://www.gotfrag.com/portal/files/24/
Install that, login to steam, steam will update itself and patch CS, then you're good to go.
NB: Those links require a GF account to DL at a 50k cap. Get Prime or search for Steam Cache on fileplanet/fileshack and you can wait in line for it.