As I read your post, I thought of the 200 Million newly indexed records that have been posted at Family Search Record Search - Pilot. April of 2010. (Yes, just in the last month and a half.)
You may have to sift through the names to find common parents, etc. But there are so many newly indexed records there for FREE.
I did find Carbonneau's in Quebec, Canada and there are many Gadbois records there too. (3 Evelina Gadbois' on 1881 and 1891 censuses).
I just found my great-great grandparents on my Gadbois line there and great grandparents on my Whitsel/Whitzel line, as well. There will be many, many more records added in the future.
Some collections are owned by other entities, so there are not images available for every record indexed. If there are images available owned by other entities, you can view them at you local LDS Family History Center or through the owner of the image collection. (Conditions of this policy are subject to change) http://pilot.familysearch.org/recordsearch/start.html#start
I apologize for the link not being there, but if you copy and paste the above address into the address portion of the internet browser, it will take you to the right place.
Happy Hunting, Yvonne