Hayzer, most .30 calibers are adequate for bear, particularly the .308 and 30-06 to mention the 2 most common. Your .50 cal smoker will work fine as well but make sure you load as heavy as you can handle while maintaining some semblence of accuracy. Most shots are over baits and will be in the neighborhood of 50 yards and under so work from there.
I'm fully booked for the '09 fall hunt but I can suggest you look at Yvon & Sons. He's in Chelmsford, Ontario, 3 hrs drive east from SSM Mi.
Year before last he went 44 bears for 46 hunters and has been putting up those kinds of stats for 40 years. Not many outfitters can match that.
Yvonandsons will get you to his website.

30-06, 308, 338 Federal, 45-70 or a Shotgun with slugs (Slug gun).

I have hunted a few places in Maine and Ontario Canada.

The best place I found with a lot of bear was Wild Country Outfitters in Wade Maine. Pete Koch the owner of Wild Country Outfitter is a top notch guy.
I am booked again for next year with him. Up close ground blind hunting, beats the heck out of sitting in a tree stand.

Check out his web site. http://www.mainewildcountryoutfitters.com/index.html