If you search on google, you can find the Q3 installer, RTCW installer(copy you pak files from the disc over after you install), UT2k3 has the installer on disc 3, Army Ops is available for download, UT has an installer at www.lokigames.com,
Enemy Territory is also available for download. 3dgamers tends to have most of these files. For RTCW, find the linux binaries, the file should be rather large, 70 meg or better, if I remember right. In all cases, you need the windows disc for these.