Wildman800, kmat, and I have been discussing where to find fuel in a long-term emergency. The following are some of the places we've come up with:

Diesel
1. Transport barges and boats. They are loaded with several hundred gallons of fuel. Check areas known for water-based transportation of goods (large rivers, harbors, etc...)
2. Trains. They are actually powered by electric motors powered by giant diesel generators.
3. Trucking firm headquarters/garages.
4. Heavy equipment storage/repair/rental centers.
5. Airports
6. Farms

Gasoline
1. Automotive repair shops (small quantities)
2. lawnmowers/yard equipment/boats. Check garages and sheds, watch out for oil/gas mixes.
3. "Fleet garages" such as taxi companies or rental car companies. Most probably don't have stored gas but it might be worth checking.
4. From cars in long-term parking areas around airports and the such.
5. Marinas. Find out if there are any marinas/boat storage places on nearby lakes/rivers/oceans.
6. Lawncare company equipment storage areas

Kerosene
1. Airports. Jet fuels Avtur, Jet-A, Jet-A1, Jet-B, JP-4, JP-5, JP-7 or JP-8 (list from Wikipedia.org).
2. Farm/feed stores
3. NASA (RP-1 rocket fuel)

Propane
1. U-Stor-It type places. Many offer propane tank refilling services.
2. Many stores nowdays have exchange programs for 5-gal propane tanks.
3. Many stores including small convienence stores and truck stops carry small propane cylinders for campstove.
4. Other people's barbecue grills. Check garages, sheds, backyards.
5. RV dealers.

Anyway, these are just some thoughts to help get people thinking of "alternative fuel depots". Please add to the list any ideas you have.

Note: I do not support blatant theft of fuel from these locations. This is to stimulate thoughts on where fuel can be found if TSHTF.

Note-2: Coming up with this list it makes me think a diesel vehicle and generator would be the best TEOTWAWKI devices for my situation. I am located near a trainyard loaded with diesel as well as several large equipent and truck repair facilities. It seems to make sense to take into account what's available when making such plans...

-Blast, in awe of Wildman800's scrounging abilities