Too much misguidance in this thread not to answer it. Best time to go there is definitely the second half of june. Thats when the park is at its best and all the little shitkids are still in school so they haven't invaded the park yet. That's if you don't like waiting in line for the t-bar. And there are lots of places to stay other than camping. There's numerous cabins/houses/small camping "houses" available, but I would recommend getting on that well in advance because they tend to get booked early. But camping is your best bet, as long as the weather is nice. Bring a tent and set it up at the camp site just 10 minutes up the road from the "town centre". Loads of nice people, loads of beer and tons of fun, both on and off the glacier. You can also go swimming in the fjord after skiing, set up a nice BBQ and get your beef on. I've spent a week of my summer there the last 5-6 years, so take it from a guy who knows whats up.