Unfortunately, things got rather bogged down at step one, buy the new hoses. At a stop sign at the top of the hill, my car died and wouldn't start up again. Bleah.
With Lori steering, I managed to push it across the intersection and into a parking lot--but the parking lot was raised, and I couldn't push it any farther. But about six men in two cars stopped and helped us push it all the way into the parking lot. People are cool. :)
One guy stuck around for a bit trying to help us get it started, but to no avail. So we walked back home and used Lori's car for our errands.
At the auto parts store, I discovered two important facts about the heater hoses for the Ford Aerostar: a) they are custom hoses that cost $27.99 each (I needed two), and b) this store did not have them in stock. However, the nice salesman offered that there was a good chance that normal hoses might work, and I could bring in the old hoses and he'd give me a judgment of whether he could just cut me a length of standard hose.
Eventually we got back to our house, called Les, and he came out. We went up to the minivan and tried to start it. It started right off the bat, twice in a row.
So we planned again to drive to his house and use his well-equipped garage to change the hoses. But I had a few things at the house that would help us; a repair manual, a few gallons of antifreeze, etc.
The car died again just as I was about to pull into the driveway. I managed to coast into a safely parked position in front of the house.
Well, then. Neither of us wanted to take the risk of trying to drive to Les's house.
Les suspected the fuel filter. So we disconnected the hoses and went back to the auto parts store for hoses, a hose patch kit, and a fuel filter.
Changing the fuel filter was fairly straightforward--Les did it, since he was running low on time.
Replacing the hoses was a bit more work, and involved moments of me lying on my back under the car with cold dirty water running down my sleeve. It also involved the discovery that the hose was 5/8" in diameter instead of 3/4", which led to a third trip to the auto parts store to exchange things. And then there was a later discovery that the custom hose being replaced was 5/8" in one part and 3/4" in another, and a difficult attempt to fit a 5/8" hose over a 3/4" flange (a process roughly equivalent to trying to fit my hips into slacks with a 30" waistline).
But eventually, all these fixes were made. The car works much better now. And once again, I'm extremely grateful for Les's help.