There are so many books out there and so many of them are lame. the personal trainer ones do seem to be about small weights and high reps. There are several good books out there for strength training:
"Starting Strength, 2nd ed." and "Practical Programming" by Mark Rippetoe
"The New Rules of Lifting" by Alwyn Cosgrove
"Optimizing Strength Training" by Kraemer & Fleck
"Supertraining" by Mel Siff
"Super Squats" by Randall J. Strossen
"Powerlifting Basics, Texas-Style" by Paul Kelso
And the book that everyone else refers too:
"Science and practice of strength training" by Vladimir M. Zatsiorsky
This list by Amazon has all these books and lots more but I can't vouch for the others:
http://www.amazon.com/Required-Reading- ... _1_rsrsrs0
Stu