+1, I bought a copy of Modern Reloading about 6 months before I got a press. Read it from the front cover to the data section in the back. I too was nervous about reloading, but reading and understanding the risks put my mind at ease.As I posted upstairs, all Lee Classic Cast presses have cast iron bases. And don't think the aluminum presses aren't strong enough to do any job you want to do.
You need at least 3 manuals and read them from cover to cover. I suggest ABC's of Reloading, Modern Reloading, 2nd ed. by Richard Lee (you'll get a copy if you by a Lee reloading kit) and Lyman #49. These are MINIMUM requirements. Several of the powder manufacturers (Alliant, IMR/Hodgdon/Winchester, Accurate/Ramshot) have on-line loading data that is safe to use, and Alliant will send you a copy of their Reloader's Guide by requesting one on their website.
Be extremely leery of loading data from individuals on the internet. There is far more bad information out there than good! Any information you get from individuals should be compared with printed data from several loading manuals for safety.
http://www.hodgdonreloading.com/ is a good source for reloading data that will help you with powder selection, but keep in mind that they only give data for the powders that they make (Winchester, Hodgdon, & IMR)