Here is the link for the Great Wolf Lodge in Niagara Falls
http://niagara.greatwolflodge.com//default.aspx?page=home
It is not right at the falls, maybe a 5 min drive, it is along the beautiful Niagara Parkway which follows the Niagara Gorge so there is a gorgeous walking/biking/skating trail which goes from Niagara Falls to Niagara-on-the-Lake (a must visit).
There is some Niagara Tourism sites you could check out that have some hotel information.
Things not to miss (from a former Niagara resident)
1) See both the Canadian and American side of the Falls (very different perspectives and the American's have goat island and I think you can walk down the side of one of the falls)
2) Do the Maid of the Mist and Jet Boat Tour. The maid of the mist will get you very close to the falls, it is sedate and calm. The Jet Boats are wild and you will get WET WET WET !!! If you are adventurous i would go for it.
3) The restaurants on clifton hill are SO expensive - like ridiculous. If you are looking for a standard chain restaurant venture out of clifton hill.
4) Niagara on the Lake is gorgeous and a must do. There are lots of restaurants (a little pricey but worth it), shopping and lots of historic homes and sites. They also have a theatre - the Shaw Festival - if you and your family are interested in live theatre.
5) If you are really adventurous you can take a helicopter ride over the falls, there is Niagara Helicopter right across from Great Wolf Lodge.
6) Take a Wine Tour/Tasting in the numerous wineries around Niagara Falls, (there a lots in Niagara on the Lake)
and last if you are already coming to Canada why not check out Toronto - so many things to see and do, shopping, museums, restaurants, so many recreation activities etc.