nightrider, ethanol in marina fuels has been discussed in another thread. I know Channel Marine was selling ValvTect Marine Fuel last year. I went to the ValvTect website and they had a locator to find all dealers selling their product.
According to their website, Channel Marine, West Alton Marina (West Alton) and Lanes End Marina (Melvin Village) are all selling ValvTect fuel on Winnipesaukee. I have no idea what the price differential is between their fuel and regular ethanol-laced fuel, either at a marina or on the street.
Here's the Valvtect website,
http://www.valvtect.com/.
There is also a ValvTect dealer on Ossipee Lake at Ossipee Lake Marina.