Seing as I have mentioned both Diana Kennedy's and Rick Bayless' books a number of times, as these are what I am primarily using to guide me, here is a link to each:
The Art of Mexican Cooking - Diana Kennedy
Authentic Mexican - Rick Bayless
There was a recent episode of The Splended Table recorded in Mexico which included an interview with Ms. Kennedy, who sounds a formidable woman! Linky
There is a good article on Bayless here by, the always readable, Jay Rayner in The Observer.
There was a recent enough discussion of Mexican salsas in the NYT. There are a couple of recipes burried in the sidebars there as well.
Finally, as I have been meaning to tackle tamales for some time, I have been looking around the web at different ways of preparing them and I found this gem.
Isn't that sweet.
It's things like this on YouTube that make you realise how wrong Andrew Keen is about absolutely everything (one look at the photo on the front of that website will probably convince you of the same thing anyway - he looks like what would be produced if Simon Cowell and Richard Dawkins had a baby, he seems to be impressed with himself in a pretty big way).