Thought I'd share my good fortune - I know I'm not alone in trying to figure out how to capture from an analog capture device in LINUX, and "How-Tos" in LINUX are fairly lacking on YouTube. Here are some command lines I've pieced together to capture - 2 for a TV card and 1 for USB Webcam. The tutorial will hopefully give you an idea on how to tweak them for your own use. As needs arise for my own further tweaking, maybe I'll post some modifications! Here they are, for your enjoyment. To use, just open a console where you want to save the video file, cut and paste, change the name of the file to what you want and add any other tweaks, and you're ready.

MPlayer/mencoder:
http://www.mplayerhq.hu

High Quality:
mencoder -ovc lavc -lavcopts vcodec=mpeg4:\vhq:vbitrate=6000 -oac mp3lame -lameopts br=256: -ffourcc DIVX -tv driver=v4l:norm=ntsc:input=1:adevice=/dev/dsp:width=640:heig ht=480 -af volume=-10 -o ****.avi tv://

Web Quality:
mencoder -oac mp3lame -ovc lavc -lameopts mode=1:vbr=2:q=4 -lavcopts vcodec=mpeg4 -tv driver=v4l:norm=ntsc:input=1:adevice=/dev/dsp:width=640:heig ht=480 -af volume=-10 -o ****.avi tv://

Webcam:
mencoder tv:// -tv driver=v4l:width=320:height=240:device=/dev/video1:forceaudi o:adevice=/dev/dsp -ovc lavc -oac mp3lame -lameopts cbr:br=64:mode=3 -o ****.avi

Getting Started in Cinelerra:
http://www.billauer.co.il/cinelerra-video-edit-quickstart...

This video was captured entirely in analog, entirely on my webcams, and entirely in LINUX (my first!) This is my third video using Cinelerra... hopefully no one noticed the difference! (less info)