I don't know if they still do or not, but the 4 season gas station off 169 and rockford road had 100 octane unleaded.
Beach's Long Lake Service in New Brighton on Long Lake Rd. (N of 694 about a mile, right next door to Irondale High School) carries 100, and 110. FWIW they also have a dyno, but not for AWD.
Bobby and Steven has race gas and e85 it's right next to NF. 3701 Central Ave NE Minneapolis, MN 55421-3928
Old colony on Broadway in Minneapolis has some race gas, don't remember what though. There is also a station by BIR that has leaded race gas.