Resources for percussion theory?

[Ringworm128]

Are there any good books or online tutorials that deal with the topic of drum/percussion theory? 

[Ransom]

I don't have much on-hand, so I'd also be interested in this. However, I did stumble across this lesson called The Dilla Feel, which deals with tuplet drum rhythms, AKA: drunk drumming.

[JohnStacy]

A good starting place is:
http://vicfirth.com/percussion-101/

It serves to introduce concert percussion, which can help in writing for them. A lot of people venture into orchestral/cinematic style writing, and write really bizarre things for percussion that sound mechanical and unmusical. Understanding how these instruments are actually played helps write for them effectively and improves the humanization of the music.

For drum set, there is a spot here:
http://vicfirth.com/a-fresh-approach-to-drumset/

Also published by Vic Firth, this is a good starting place to understand drum set. If you have a functional understanding of how drum set is played, you can write and sequence drum parts that don't sound mechanical.

Then just a general percussion thing:
http://vicfirth.com/education-resource-library/

These places are a solid place to start to understand percussion.