i haven't had issue finding diesel around chicago... i just have issue finding the right kind... it seems quite a few of the stations around here mix biodiesel in B5-B20... and alot of the stations have the wrong handle (the big truck handles) instead of the green one that fits...

but what i found best was i just pay the 200 a year for bmw assist.. whenever i need diesel and don't know where to get it I just call the concierge and they'll do the leg work, down to calling the station and finding out what kind they have etc...

-john