Hi Sarah... I'm not a mtn biker but I know LOTS of people mtn bike in Mission Trails Regional Park ... not sure how good it is, but I'm guessing OK since everyone goes out there...
you may call the local Trek store and ask them to forward some maps to you as well... I think the local shops have them in email format now to send out...
and here's some ride links as well:
http://www.trails.com/activity.asp?area=14947
http://www.sdmba.com/ride_guide.cfm
have a great time...![]()