Resources:
NMA Traffic Calming Fact Sheet ( PDF )
Free to download, print & distribute.

Federal Manual on Uniform Traffic Control Devices
The MUTCD contains standards for traffic control devices that regulate, warn, and guide road users along the highways and byways in all 50 States.

RADA
Road Access For Disabled Americans

CalmingRisk.com
Provides traffic calming information often that is often overlooked or deliberately suppressed.