This is a great reference page for Allegro.  It basically shows you all the Functions in Allegro in one quick reference page.  I just tried to print it out, and it is approx. 13 pages.  This is an excellent resource when ever you are game programming in Allegro to keep next to your keyboard which will remind you of the available Allegro functions.

Visit the site if you like, but since it is public domain, I also made a PDF of it and am hosting it here.

Here are the chapters:

1. General
2. Graphics
3. Bitmap Commands
4. Video Modes
5. Double-Buffering
6. Colors
7. Timers
8. Text Output
9. Keyboard Input
10. Mouse Input
11. Sound Output
12. Collision Detection
13. Translucency
14. Angles and Math
15. Examples
16. Technical Information