Any of the SM tutes are gr8, but for free ones... I would look at:
Learning Maya or
Digital Tutors
Also look into the Maya Foundation Book by Alias
Chris (formerly R@nSiD)
Twitter
When the power of love overcomes the love of power the world will truely know peace - Jimmy Hendrix
Winner SM VFX Challenge 1
3rd Place SM SteamPunk Challenge (May 2007)