there are two i know of for sure, there is a tournament on pelican lake, the site for that is
http://www.wiicefishing.com/, and the other one i heard about was the one in brainerd that you mentioned. I fish right around pelican lake all winter, dont usually venture out there because we never have any luck on that lake, ice or open water fishing. As you can see from the results from the tournament last year, the winning fish was a perch, as was every other fish that won a prize. hope this helps.