Web sites, I guess you would have to do a search. I have 2 good books that I practically carried around with me all of the first year when I moved to Duluth.

1. Wildflowers of Minnesota Field Guide by Stan Tekiela. I think I bought this at one of the state parks, but it is probably at the bookstores, too.
2. What's Doin' the Bloomin? by Clayton & Michele Oslund. A Pictorial Guide to Wildflowers of the Upper Great Lakes Regions, etc. etc.

There are probably some regional books that focus more on praire-type flowers or woodlands.

I have tended some pretty nice weeds, but also some noxious ones. They can all usually be pulled. Have fun.

a.

Welcome. If you Google Minnesota Plants or Wildflowers of Minnesota you'll get some of the DNR's listings with pictures and info.

Also, if you can post pictures, there are some really knowledgeable people on the "Name that Plant" or "Weeds" forums.

These websites all have pictures but you'll have to pick names at random until you become more familiar with plant families.

Plants by month of bloom:
http://excursion.websitewelcome.com/~prairie/plant_info/Month/month_main.htm

Searchable plant database (you can specify your criteria, selects from 230 plants):
http://bluethumb.org/plants/?

University of MN Extension Service searchable database (don't neglect to select "Herbaceous")
http://www.sustland.umn.edu/plant/plantdata.asp

HTH (Hope this helps)