The periodically staffed Polebridge Ranger Station is right near the no-longer-pole-constructed bridge over the North Fork. Stop here for backcountry permits, trail information, or a chat about the local wolf packs.
Drive in from the park on Camas Creek or Inside North Fork roads; the Inside North Fork is rougher, but there are some campgrounds along it. From Columbia Falls [1], the Outside North Fork Road, with good views of the Livingston Range, leads to Polebridge [2]. Blankenship Road connects the Outside North Fork Road with West Glacier [3]. In the winter, Outside North Fork Road and Blankenship Road are plowed.
Links:
[1] http://www.moon.com/destinations/montana/missoula-and-northwestern-montana/north-flathead-lake/columbia-falls
[2] http://www.moon.com/destinations/montana/glacier-national-park/north-fork-the-flathead-river
[3] http://www.moon.com/destinations/montana/glacier-national-park/west-glacier-and-the-flathead-river-middle-fork