Some of the plants that butterflies are attracted to are petunias, zinnias, and the butterfly bush. You need to remember butterflies love the sunshine, so plant in the sunniest area possible. Good luck!!
http://bloomiq.com/content/butterfly Found that little diddy for ya :) I don't know where more of these places are, but my sister went and visited the Butterfly House in Canada. It's not named the Butterfly House, but I can't think of the name right now, it's kind of near Niagara Falls.