I'm in the process of starting a small, rural WISP. My contact details are in my profile... no 'road-map' though. It can be very different depending on your situation. Still, I am interested in collaborating with others!
One of the hardest problems with this would be getting connections to customers. I wonder how effective wireless connections could be. I know of a couple companies that do it for whole apartment buildings but I've never heard of it for just one house.
Wireless for houses is, especially in rural areas like where I live. I am in the process of starting a WISP right now to serve my rural area.
The biggest challenge in any area is how crowded the spectrum is. Crowded spectrum will ruin your available bandwidth.