Gathering of Developers has recently released Hidden and Dangerous Deluxe as a freware game http://www.gathering.com/hd2/hddeluxe.html (aprox 260 meg) it's a good game to learn from as well as just sitting down to play.

If your a dial up user ( like me) i recomend you use the fileplanet download site. thier download manager lets you continue the donwload if you get disconnected before finishing ( besides downloading usualy 2X normal dialup speed)