I am completely aware that CS used to be a third party mod, I played it from Beta 1.2 (aka Beta 1.9) to Beta 7, watched as it got transitioned over to a Valve game, and played v1.0 to 1.5, and even got into the limited beta test of Steam and v1.6... I kinda lost interest at this point and have only started playing again with friends due to CS: Source, but that's besides the point. Steam of course has now been fully deployed for quite a while, hence why I'm recommending it... I wouldn't have done so during the beta test lol
Anyway, as far as I know, every single copy of Half Life came with a CD key, and if it didn't, I'm sure you can get one from Sierra/Vivendi/Valve/whoever is supporting the original Half Life now, otherwise you've got some hell to raise.
