Oh come on. Everyone knows it's from dashboards from alien spacecraft that crashed in area 51.
Seriously, while Woodcraft and Rocklers have very nice high quality wood, they are usually hideously expensive compared to wood suppliers. Kettle Moraine Hardwood is also a good source just south of Milwaukee.
Yes, and there's one north of Milwaukee by Slinger. The selection and prices are much better than at Rockler's, Woodcraft's, or home improvement stores. They'll also rip an edge or flatten a side for you for very little extra. That's why I recommended the poster try to find a local mill.