MORC has the most current trail descriptions. IT looks like a Google Maps layer so I hope there's a way to add it to my Google maps,
Friday, April 9, 2010
Mountain Bike Trails in Minneapolis-St. Paul is an older set of reviews by Todd Murray, who I know of from the Minnesota Inline Skate Club. It's not been revised for some time, but it mentions some trails very few people know of (such as the scattered trails around Minnehaha park).
Ramsey County Parks (includes Saint Paul, MN) page now includes a link to a Ramsey county bike trails map. Of course it's a poor cousin to the Hennepin/Minneapolis trail system.
There's also a cross-country trail map and locations page.
Mountain biking is only allowed in Battle Creek regional park. I think the easiest entrance to that system is from Winthrop Street, south of Upper Afton road and North of Lower Afton road. There are also two single track entrances on Point Douglas Road though they may be tricky to find.