This thread is already filling with interesting information on starting a rock garden. The photos and and plants lists are great.
This link has great sources of information on creating many types of rock gardens. I have been there, it is an amazing place for learning how to make simple gardens and up to more challenging rock gardens.
http://wildgingerfarm.com/
You will find a list about half way down the page.
I have been planning a simple rock/gravel bed in my front yard this coming spring/summer.