http://pure-gas.org/
You can also get airplane gas (AVGAS 100LL)
Word of caution about that site. Anyone can register including dealers of the $30/gal canned fuels. Its not all actual gas stations. 80% or more of the stations in the USA are 10% blend in all grades so the vast majority of people will have to drive considerable distances just to get some.
Follow this:
Small 2 stroke equipment like chainsaws/trimmers, run dry. Make sure you were using a 2-cycle oil with a stabilizer additive (most have it these days).
Larger 4 stroke yard equipment, use a quality fuel stabilizer (not Stabil brand), purchase fresh gasoline, mix the two according to instructions. When the equipment is going to be used for its last time top it off with the fresh fuel/stabilizer and let it run for about 5 minutes to cycle it through the fuel system. Store it FULL of this new fuel with stabilizer.
This keeps the gaskets and fuel line supple, prevents varnish and corrosion, and stops tank sweating as well as rust (if its a metal tank).
Doing nothing causes, at the very least, hard starting and debris to settle in the bowl from the inevitable corrosion that takes place as fuel ages. 3 months or less, you'll probably escape with this method for quite some time, 5-6 months or more and you'll absolutely have issues. For me yard equipment is parked from November to March or April so that's pushing it.
Running dry exacerbates the above because of the ounce or two left in the carburetor bowl that couldn't be reached by the nozzle. This tiny amount of fuel can turn into a thick varnish in just a few months which eats into the bowl and the carburetor body. The only real way to run a machine dry is to completely empty the fuel tank then dismantle the carburetor and dry it completely. When compared with the effort required to just top it off with fresh fuel/stabil you can see which I prefer.