Apparently he is too humble to promote himself, but former letsrun.com regular northernstar (AKA John Davis) who also writes the blog
http://www.runningwritings.com/
has just published the book Modern Training and Physiology for Middle and Long-Distance Runners.
He's probably best known for being "Kellog interpreter" and has complied a PDF with all of Kellog's posts and articles available for download somewhere. I'm partial to his injury series, such as this one on achilles tendinitis.
http://www.runningwritings.com/2011/08/injury-series-eccentric-exercise-and.html
Link to book:
As Tyler Cowen would say, self-recommending.