As mentioned, there's not a ton of riding in the Edmonton area, but htere is quite a bit within 2 hours. Brazeau, Edson, Vega, REdwater, Bruderheim, Iron Horse Trail, Cougar Patch, Alder Flats, Medicine Lake to name a few.
There are also some small trail systems in the Lac Ste Anne Area but Stanger Hills is the only one with publicly available maps. Of course, being relatively close to Edmonton they are in need of a lot of work. The Lac Ste Anne ATV club is having their 2019 AGM on Mar 24th. You might be interested in attending and becoming involved - it's a great way to become an active part of the community, meet people, and learn a bit about trail sustainability: https://www.lacsteanneatvclub.com/event-3304609
That's right, forgot to mention them as well. Seems to be a club that's picking up really good steam. Whitecourt is not too far from Edmonton with a fair amount of trail.