Garmin has a mapping program that includes backcountry roads. It's an expensive option however. My 2001 Garmin unit (which has over 30,000 miles on it!) uses breadcrumbs as well.
You could try this software for Garmin, which is the USA TOPO:
http://www.garmin.com/cartography/mapSource/topo.jsp
Here's an example from the online TOPO WEST (Baldwin Lake southwest of Buena Vista, CO):
http://www.garmin.com/cgi-bin/mapgen...&rz=0&k=1&sc=1
You can see that the trails show up as dotted lines. Not the best, but at least you can get an idea of the topography, and have a general idea of where you're going. The hardest thing is if the maps don't agree with the actually terrain. I had a hell of time out there trying to find my way on some trails as they branched more than shown, and some of the plotting was inaccurate. I have a lot of notes on my maps....
