Mr Warman,
 I defer completely to your experience (and my own) on these vehicles. They aren't
for the uninitiated or inexperienced. I agree totally with the first part of your post
(4 hours, clean the MAF, etc.) The Aerostar is not the ideal vehicle for learning, but
more a "trial by fire" for a DIYer. If you can work on "that one" then...
 The OP was obviously less than a DIYer, by admission, and wondering abouthow to
possibly reduce an, IMHO, out of line repair bill. No matter how you look at it, $600
for a basic tune up(plugs, wires, filters), on an Aerostar or any other vehicle, is
just a little tough to swallow.

In all honesty, I'd be looking at 4 hours (at least) for labour.... others
may quote less but rush the job leaving a host of trouble in the making
behind - there is just no room at the distributor for rushing (anybody ever
look at that dinky little hole???) - especially if the tech is to run the
replacement wires correctly as to avoid possible RFI enterference with
computerized signals as well as avoid having the wires contact hot exhaust
components (and failing shortly there-after).

At the same time, I would recommend that the shop inspect and clean (if
necessary) the sensing elements in the MAF (mass airflow) sensor... after 13
years I would imagine that they are wearing a pretty hefty "fur coat".

Other considerations - has anyone laid with their face pushed into the 13
year old carpet between the front footwells? I might suggest, if the van is
taken to a shop, some attempt be made to ensure there is no refuse on the
front floor and the area vacuumed..... It can be nothing less than amazing
as to what some customers expect us to endure.

While a factory manual (the "pirate" CDs and DVDs are plainly labelled "Not
For Resale"... I leave the morality up to the individual) is good
intruction, it is not a replacement for experience or patience..... For
someone learning how easy it is to damage new parts, I would NOT suggest the
cramped, difficult to maneouver in engine compartment of the Aerostar as a
classroom.

FWIW, in our area, four hours of shop time would be nearly $400 (plus tax).
I cannot vouch for how good the tech that performs the service is going to
be, but going to a shop that lowballs the price wont usually have
concientious employees.

Of interesting note.... even after removing the access panel between the
front footwells, it is still extremely difficult to view much of the
distributor cap... the parts that matter cannot be viewed without removing
the cap altogether.... considering the time spent and the difficulty
resulting from the cramped quarters, I wouldn't remove the cap unless a new
one was going to be installed. I am left wondering about the accuracy of
this particular diagnosis...

 I agree, $600 is WAY too much. Around $300 would be reasonable because the Aerostar
is so difficult to work on, considering dealer labor and parts. Being a woman may make
a DIY repair easier, as your hands and arms may tend to be smaller than the average
gorilla male technician. ;)
 I did a quick search for manuals on Ebay. There are a couple of paper EVTMs
(Electrical diagrams) but I didn't find any of the main service manuals in paper form.
For a complete set there would be 3 books (EVTM, PCED, and Volume H). There are lots
of CDs though, and they cover all of the material in the 3 books. The Ford service
manuals have been available on CD since 1992. They take a little getting used to but
are the same info as in the paper manuals. Here's one:
http://makeashorterlink.com/?K24352ADD . This is a (possibly illegal?) copy of the CD
used in the dealerships.
 To do the tune up may take up a weekend the first time if you havent attempted to
work on your car before. It would be good to have a knowledgable friend for backup.
With the proper tools, as mentioned earlier, it should cost ~$120 using good parts.
Use Motorcraft plugs and good (~$70) plug wires.
Good luck.

$600 is a lot for that; it should be $300 or less for plugs, wires, cap
& filters. If you want to try it on your own, get the FACTORY Shop
Manual from eBay (used) or from www.helminc.com (for new). You should
also have a set of socket & open-end wrenches, a test light, a torque
wrench, and a code reader. The first thing I would do is put in fresh
spark plugs, which go a long way toward helping a car start. Another
design weakness preventing a quick cold start is the Idle Air Control
valve that wears out over the years & miles.

my problem is that on some days my van wont start so im thinking
distributor cap. now i took it to a repair shop and they said that was the
problem and also i need a tune up and wires and they quoted me $600.00 to
put new wires and new cap and air filter and fuel filter so my question is
$600.00 to much to pay?.and is there any way i can do it myself with a book
or anything else. by the way i am a woman could that be why the price is so
high. please help.