Typing "AP US History" into a search engine will bring up hundreds of thousands of pages. The list of links below contains some of my favorite. If you have a link you would like to suggest, please feel free to do so.
Patrick Rael, Bowdoin College Reading, Writing, and Researching for History: A Guide for College Students
AP US Outlines & Charts
Strategies for reading and recalling information from your history textbook and primary sources Social Studies Reading Room
A tremendous free resource. Check out the note card section. Approximately 1600 AP terms. AP US Notecards
Guide to Writing History Papers
Writing a Good History Paper
How to Write a History Research Paper
Research and Documentation Guide
The Nichols School Library page (link to Online Course Reserve)