Not possible man, you need Steam to play Counter Strike: Source. You need to install the Steam client onto your computer, then either purchase games in store or download them through steam (There is alot of games on steam, many classics also), many critisize it but I've never really had problems with it. Also, say you have Half Life 1 but the cd is fucked and don't have it installed on your pc, just put in the serial in steam and the game downloads. And you can take your collection of games with you whenever you can find a pc that you can install steam on that has a connection to the internet. I think I have paid for 3 games total and have about 20 that come with the games (Day Of Defeat, HL2 DM etc).