Unfortunately hadn't had time to get round to this one quite yet, but I was also planning on getting in on some quadruped action. I'm not particularly confident with quads yet, so I was doing a little research. Thought I'd might share (click the text)...
Interactive 3D dog skeleton
Richard Williams on basic quad movement (video)
101 Dalmations page from Andreas Deja's blog
Muybridge, animals in motion (full thing online)
Tips on drawing and animating quads
Dogs on treadmill (video)