This is by no means an exhaustive list, but it should provide a nice starting place!
One-Size (adjustable diapers)
Paid Patterns:
Cutie Patootie
KCK One
Little One Size Diaper Pattern
Mosaic Moon
Free Patterns / Drafting Instructions:
Little Bean Bum
Sprout Snap (This link goes to their shopping cart, but the pattern's free)
Front-Snapping Sized Diapers
Paid Patterns:
Little Starter Cloth Diaper Pattern
Very Baby Cloth Diaper Pattern
Free Patterns / Drafting Instructions:
The Cloth Revolution Diaper Pattern & Mirror Image for printing full pattern.
Goodness Gracious Diaper (Prints out on Legal-size paper)
Ottobre Free Diaper Pattern
Tutorial: Prefold to Fitted
Sew Your Own Diapers Fitted Front Snap
Side/Hip-Snapping Sized Diapers
Paid Patterns:
Fatty Cakes
Free Patterns / Drafting Instructions:
LCT Tighty Whitey Hipsters
Other-Type Diaper Patterns
Paid Patterns:
Free Patterns / Drafting Instructions:
Not So Flat Wrap (or Here)
Quick Snap Flap (Flat-type diaper)
Aquarius Swim Diaper (Pattern)
Training Pants Patterns
Paid Patterns:
Potty Dance Pants
Stellar Transitions
Tinkle Time Trainers
Free Patterns / Drafting Instructions:
Ditto Daddy (not waterproof)
EasterBunz