I've found two places that seem pretty good, for us. The first couple runs we went on we parked near 115th Ave off of 44th St. We ran north down a powerline corridor that parallels 44th St for about 1/4 mile then east on 115th Ave (on both the snowmobile "trail" and road) for about 4 miles turning around near a llama farm
(which made turning my dogs around really challenging).
On Saturday I also ran them north of 115th Ave. and 44th St. on a two-track that heads north on the west side of 44th St for about 2 miles. Much of these trails were either sand or leaves churned up by snowmobiles - hard work, but still fun.
We also went back today and did about an 8 mile run on the trails around Ely Lake and the campground coming out onto a snowmobile trail along 116th Ave for awhile. A lot of the trail around Ely Lake was flooded out and frozen over