W:
Yes, there is a great many free (digital) pubs available, which in fact may be as much of a problem as a solution. Neither the AIM nor the FARs strike me as good introductory reading for the simple reason you apparently have no grounding (in learning theory terms, no 'intellectual scaffolding') on which to hang the information and interpret the jargon.
"[I] intend to purchase a LSA and get my SP ticket. I would like to get a jump on things and start learning as much as I can..."
Since you didn't mention any previous flight training or aviation exposure, IMO there are two distinctly different areas of learning you can tackle now. The first is an introduction to general aviation, how an aircraft 'works', and the airspace system in which it flies. An excellent reference, published by the FAA, is the Pilot's Handbook of Aeronautical Knowledge. You'll find it here -
http://www.faa.gov/library/manuals/avia ... t_handbook - altho' my suggestion is to purchase the hard copy. The reason is that you might benefit by 'shopping' among the chapters based on your own curiosity and interest, rather than reading it like a novel, beginning on page 1. It's well illustrated, very understandable and comprehensive.
The second area is investigative & experiential rather than intellectual. What are your training options (in the Amarillo area, if that's where you intend to remain) and how do you personally feel about flying? Paul's website is an excellent resource but consider that a starting point. Keep in mind many parts of our country do not offer Sport Pilot training and/or they lack LSA rental aircraft for training. (A brief Google glance at Amarillo's training options leaves me unimpressed with what you will find in your area). Most flight programs offer an introductory flight at a special price. I'd recommend you do at least that - perhaps Lesson #1, as well - just to see how you feel about flying as a pilot & as a student vs. a passenger. If this idea still highly appeals to you, great! If it doesn't, think of all the time you've saved yourself.
Purchasing an aircraft you'll end up being satisfied with, long term, before knowing much about flying is a challenging task. OTOH it's do-able with some knowledgeable guidance and, assuming you'll be flying for a while, can significantly reduce the cost of learning to fly. Ultimately, a better option for you might be to relocate to an area with a well regarded SP training program and complete your training there (vs. staying in your local area if it lacks a good SP program). Some locations even have temporary living accommodations available for students who want to do this.
Finally, consider whether you can qualify for a Private Pilot License. If that's an option, it might open up alternatives for you in your local area that otherwise aren't available.
Good luck to you!
_________________
Jack
RAF Florida State Liaison
Please visit
www.theraf.org