I hope this will be of some use to one or two of you.
If you've ever found an animal track and wondered what made it then check out these links:
BBC Wildlife - Information on UK animal tracks.
PDF from BBC - Supporting the above link.
RSPB Animal Tracks - How to take casts of tracks.
Beartracker - Mammals - good selection, USA based.
Beartracker - Birds
Beartracker - Amphibians
Beartracker - Reptiles
Beartracker - Insects
Beartracker - Humans