This link lists a bunch of hotels/motels in Kitchener/Waterloo.
http://www.kitchener-waterloohotels....com/index.html
I have stayed in the Howard Johnson Hotel and in the Knights Inn (HoJo is a better hotel). I can't remember what we paid in the past, but the website shows a range of some room pricings.
For any team worried about crossing the border I know it can kind of seem overwhelming initially, but as Karthik said earlier FIRST Canada is willing and able to help however they can, and I got two robots back and forth across the border last year a few times and for the most part it is straightforward.
Any questions/concerns I'm willing to help out as well.
GTR is a nice event, but personally I've always liked Waterloo better. More matches, better teams, and a friendlier, closer atmosphere.