This isn't a campsite review exactly, but it is a suggestion of where to go if you're near the west side of Glacier National Park (GNP)...it's not a developed campground either.
Starting from the west side of GNP, near Whitefish, MT, head east to Columbia Falls. You should end up on 9th St, also known as HW 2. Keep an eye peeled for state highway 486, which you'll want to turn north onto. This turns into North Fork Road, a sweet ass road that gets all gravelly at some point and will take you up to Polebridge, MT, with is 30ish miles north.
The road somewhat sucks, which seemed to deter the riff raff (ie - normal people / casual travelers / yuppies.), but it's well worth the trip. Polebridge is a collection of houses, a mercantile, and a hostel. It's a very small town and is near the Polebridge gate to GNP. The hostel is run by a laid back Scandinavian guy named Ollie. For $10ish you can rent a canoe, borrow Ollie's red Ford pickup, and drive into Glacier to go canoing for the day on Bowman Lake. Then when you're done, just ask if you can campout on the hostel's land. When we (we being Jenn and I) were there, he offered before we even canoed, so you may not have to ask. I can't see it being an issue though. He seemed to like VW buses.
At night, the Mercantile seems to be the place to go. They have wine/beer and also support a byow (bring your own whatever) policy. Expect the breaking out of instruments and general
merriment to ensue. Or spend your time camped out by the hostel, which is pretty much on the river. Also, if you drive back down the N Fork Rd, there's a bar/pub type place that has good food and good beer for a decent price. I can't recall the name of the place, but it's on the westerly side of the road about 2-4 miles (ish) south of Polebridge and has a large gravel parking lot.
It is also possible to camp at Bowman Lake I believe, and it looked to be a nice place. But given the amount of National Forest land around, as well as Ollie's hostel, we didn't have the desire.
The sign you see coming into Polebridge