Learning to Patch?

[Dice]

Knowing Most all C Syntax languages, and rough assembly (I need to brush up) I'm looking to learn how to hand create simple exes, and also learn about executable patching.

I've played with DLL injection and hooking, but never directly modifying an executable or dll.

Where would be a good place to start learning how to patch?

Can anyone recommend a good starting book or other resource?

Thanks much!

-Dice