Locations for Ethanol Free Regular Gas

Here's a website listing ethanol free gas across the country and in Canada: pure-gas.org

And here are some local (western PA) stations:

Rudolph's Auto Repair
3750 Gibsonia Road
Gibsonia, PA 15044

Purvis Brothers' Stations
Mars Service Station
321 Mars-Valencia Road
Mars, PA 16046

Planet Mart #21
642 Pittsburgh Rd (Route 8)
Butler, PA
Open Monday through Friday 5:30am to 9pm
Saturday & Sunday 6am to 9pm

Planet Mart #22
404 N Pike Road
Sarver, PA 
Open Monday through Friday 5am to 9pm
Saturday & Sunday 6am to 9pm