I have truly found a love in exercise science, physiology, biomechanics, and training in general. I may very well be making it a career path down the road.
That being said I have done lots of reading.
I've come across many great resources, almost everything has some value, but some have far more value in them then others.
You will find for almost any question you have you can find an answer, and then probably a dozen more. This is why there are great all in one manuals, they simplify things and take the guesswork out of programming, your just going to have to cough up some cash.
If you take the time to read, the internet has become a great source of knowledge. Most of the well known trainers write A LOT. They will often include some endorsement to their own products but all and all they are extremely informative.
A lot of guys will respond to your emails if you have a few simple questions. They were all aspiring athletes at some point, and it's salemanship too.
In the reading you will find things are geared towards different things. Athletes, bodybuilding, out of shape people, ect, but you can almost always take useful information away from the reading.
My favorite places for information (most of these are in my bookmarks toolbar haha)
Some of the following are conglomerations of different authors writings, others are sole sites of one person.
You will also find each person has a different style, some prefer certain lifts, some lean towards brute strength and force, some prefer to be corrective to balance out posture and such, some are all about the prehab.
I find it's best to take something from everyone rather than everything from one. That's just me.
Joe Defranco- defrancostraining.com (This man has some of the most amazing results for athletic improvement of anyone)
Eric Cressey- ericcressey.com and http://ericcressey.blogspot.com/
He recently posted a newspaper article about 4 of his clients who all played baseball at the same school. One of them was a lefty that gained like 8 mph going into his senior year, he wasn't going to play college, but after his offseason he will be.
Mike Robertson- http://www.robertsontrainingsystems.com/articles.html
John Berardi- http://johnberardi.com/articles/index.htm
This man really knows nutrition. What I loved the most about his resources is he was actually a skinny guy. I find a lot of guys think they know all this stuff about how to get stronger and bigger, but they were big all the time. Berardi tells it like it is.
Conglomeration of writers, a lot is powerlifting specific yet there is so much great information from some of the most experienced individuals int he field.
T-nation - http://www.t-nation.com
Conglomeration of writers. There's lots about body building and just looking good, but there are SO MANY ARTICLES on the site you could read for days about sports enhancement.
If you would like to look up studies on anything in the world of sports, this is a great spot to find abstracts and even whole studies.
Learning from studies will help you apply knowledge.
There's tons of more great trainers out there, heck I know I'm leaving out some guys that I probably read today.
You will also find most of the top guys in the industry don't do tons of marketing like most of the gimicky fitness industry, they get results and their business grows.
Also many of what I would consider the top guys are "networked" and refer to eachother a lot. They do roundtable discussions, and seminars with some of the brightest minds around, so I mean collaboration makes sense to me.
The list goes on an on really, again this is why the all in one manuals are so handy, guys take their years of experience and knowledge and put it into one spot.
Good luck man, reach for the stars!
Hope I didn't make things more confusing with this long post.
I could probably make a list of some of my favorite articles if you would be interested.