xcam was the only one of three (xcam, gqcam, xawtv) that worked for me. After I run xcam and change from gray to color, I can run gqcam or xawtv and they work (once). I have to run xcam again to reinitialize.

Try usbview to make sure something is found when your camera is plugged in.\

Try xawtv -hwscan to see if /dev/video0 shows up.

Try building the entire xawtv package... It really is not too bad.