Here are some links that we find helpful:

Hal Higdon Marathon Training Programs
Hal Higdon offers free marathon training programs online.
http://www.halhigdon.com

Pacific Coast Trail Runs
The PC Trail Runners are a husband/wife team that put together some of the most fantastic trail runs we've been on. Their runs occur in Northern California. The Trail Trudgers has, in the past, trained for and ran in a few of their races and we see no reason to change a good thing.
http://www.pctrailruns.com

Active.com
Many local races post their runs on Active.com. You can search for races in your area as well as sign up for them. They do charge an additional fee for using their signup system (usually around $5).
http://www.active.com

Sacramento Buffalo Chips Running Club
The Buffalo Chips are a great running club in the Sacramento area. They claim the title of Sacramento's largest and oldest running club.
http://www.buffalochips.net