If you want to learn from a book then the Kuhnhausen book is probably as good as you will find.
If you prefer video then the American Gunsmithing Institute (AGI) sells videos.
I'd get both unless you never intend to do another trigger job after this one. It's not hard to do but it is tedious and requires close attention to detail to get it right.
You will also need a few specialized tools, but none are particularly expensive. We're talking India stones, Hard Arkansas stones, feeler gauges, and a small fine-cut file with one safe edge. You should be able to get everything you need for less than $100.
One of the simplest solutions is to buy a Chip McCormick matched hammer and sear. This will automatically reduce your stock trigger pull weight and give a nice crisp release. If you have a trigger better than this then you don't need to work on your gun. Last time I bought a set it was $35 as I recall.
Finally, here's some good info that won't cost you anything:
http://www.thehighroad.org/showthread.php?t=61238Holp this heps. Good luck with your project.
-Lee