One thing to keep in mind is that these trucks are 10-15 years old. If it's all original, even if the previous owner has taken good care of everything, there's likely to be a lot of maintenance that needs to be done. Not rust etc, but normal stuff that just breaks or wears out after 10-15 years like radiator, air conditioner, starter, water pump, fuel filter, O2 sensors, axle seals, etc... and with the '93+ you have the whole head gasket thing to worry about. (I love the 3FE!)
They're GREAT trucks once all that stuff is done, but if it doesn't need doing at the moment you buy the truck, it probably will pretty soon. If you accept that up front you will likely fall in love with it!
Also, just FYI - ih8mud.com is an awsome source for info on doing your own wrenching. I am a faaaaaaar cry from being a mechanic, but my time spent learning how to do things myself at 'mud has probably saved me $3000+ in labor costs over the past couple of years.