first download the half-life and CS
then use gcfscape to extract all the files from the half-life.gcf and counter-strike.gcf to the same folder
then you'll be able to run the HL directly, and run CS with "hl.exe -game cstrike"
if still have problems, search for filesystem_stdio.dll file in the Steam install dir and copy it to the HL main dir
as you already have the HL cd-key this shouldn't be so bad
Well, if you download steam from www.steampowered.com you only need to longin once after being fully updated, n' then when steam tries to login it'll say: "error, cannot connect to steam." then just click "offline mode" and there you go, you'll never have to worry aboot logging online onto steam.
Later-a-much, and LONG LIVE THE D!,
(Link>>>MarD's Moddin' Site<<<Link) MarD
or when u start steam make sure ur internet connection is disabled whiel it starts up then it will come up with a dialog box asking to retry or go offline