https://67.15.36.49/team/Tutorials/ra...ing/ramy03.asp
https://web.alfredstate.edu/ciat/tuto...ngPolygons.htm

These two are ok, you could also download the video tutorials from this site.

Aslo, Mike's book on game art with maya has a good uv editor section.

Learning-Maya has links to several, but I can't vouch for all of them: https://www.learning-maya.com/texturing.php