I took up the challenge last July, but I started reading about hoof care before that. I started with a rasp only ( only taking a little at a time, much more forgiving then nippers ) and posted here for the expert eyes. I unfortunately didn't have a good trimmer in my area that I could study under. My 2 horses have pretty "normal" feet, with no serious issues, so I was comfortable with learning on my own as I went.
I liked ( and referred to often ) the following websites. I started by studying the anatomy and proper function of the leg, so I could better understand how things should work vs. how they shouldn't. I looked through many case studies, seeing the progress and how the issues were taken care of.
ANATOMY - The Natural Hoof - Barefoot Horse Riding
Bare Foot Horse
Iron Free Hoof
Pete Ramey writes about white line disease thrush navicular disease hoof balance
Pete Ramey makes healthy hooves on barefoot horses heals founder in horses
The Horse's Hoof, News for Barefoot Hoofcare
Barefoot Hoof Care - Page 1 ( including ELPO hoof mapping page )
I'm still learning, but in 3 1/2 months this was my progress:
( left - July '12, 11 days after farrier trim, resized to match "after pic", black line is the same length/angle.....................right - October '12 )