I had the same issue a couple of years ago. I found two ways to get the info. I looked up many of the clubs there and found their maps, which most had good mileage on them. The other place is through MSA website.
http://trails.msasnow.org/trail_conditions/trailreports.asp
There you can click on each of the dots, it will give you that areas trail reports and at bottom there is map that you can access and print out. Has really good info on them too, such as food and gas (verify gas before you assume it is going to be there).
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Here are a couple of other maps.
http://www.midnr.com/Publications/pdfs/ForestsLandWater/SnowmobileTrailMaps/western_up_snowmobile.pdf
http://www.midnr.com/Publications/pdfs/ForestsLandWater/SnowmobileTrailMaps/eastern_up_snowmobile.pdf
I like these for large overall maps of the UP