Not a fitness writer, but great for explaining in simple easy to follow terms are the books by Brad Walker on stretching and injuries. I learnt alot by reading his books. Would be great if they were more indepth but a little google searching can turn all that around. It was through reading his book on injuries that I found out my suspected shin splint/tendonitis was actually caused by a foot muscle inbalance which I was able to experiement with- I can now run with no pain!