If you are interested in TDI's check out
www.tdiclub.com , but be warned they tend to have "form" responses, most likely due to the fact that the search SUCKS.
<Following information is opinion>
DO NOT BUY AN AUTO TDI Get some other car if you want an Auto, I own 2 auto's in G***ers, they are great, but the TDI Auto SUCKS
</OPINION>
Best aero on top (claimed by TDI club members)
Jetta Wagon
Jetta
Golf
New Beetle
The 99.5~2003 ALH Will get better economy
the 2003~2006 PD Is less forgiving with alternative fuels (can definitely still be done) and gets worse economy, however it is smoother running, and more powerful.
If you do get a 2003+ MAKE SURE the correct oil was used, otherwise plan to throw an Cam, followers, an maybe injectors at it.
Don't be afraid of High mileage cars, mine still has plenty of cross hatching on the cylinder walls, uses no oil (can't tell differance on stick in 7,500 miles) all at 170,000 miles on the clock.
FYI they are one of the easiest cars to work on I've encountered, parts aren't bad $ wise. check out
www.tdiparts.com
Timing belt DOES actually require special tools, no harder than most, but does require the tools. Factory is 60,000 miles, but for only a few more dollars you can get a stronger belt and larger tensioner that makes the belt good for 100,000 miles.
I don't know what they make the brakes out of, but they last forever, I've talked to SEVERAL people with over 250,000 miles on original pads/ rotors/ everything.
Clutches are long lasting as well.
Electrical system has a few quirks, nothing serious, or hard to fix, but there are a few things that fail on EVERY car.
MAF's do go bad, not worse than an adverage car, Temp sensors seam to go bad more frequently than most autos.
NO Spark Plugs, NO Wires, NO CAP/ Rotor NO O2 sensor
Mufflers rust easily on these cars, but to be honest you can barley tell the difference once it is gone (replace with straight pipe).
The ground clearance is Lower than average, may want a skid plate if you often encounter very bad roads
Handling is Quirkey, but very FUN
Oil changes on an ALH are cheap if you do it yourself, Oil is available at Walmart, and the job cost about $22 for a 10,000 mile oil change. Unsure about PD cost.
Interiors tend to rattle, some TLC is required if that bothers you.
Real world, adverage drivers MPG (Well educated guesses)
ALH 5 speed 42 City 46 Hwy
ALH Auto 37 City 40 Hwy (good friend has one, she gets worse than this)
PD 5 speed 39 city 44 Hwy
PD auto Ask someone else
PD Triptronic Ask someone else
I hope that makes it easier on you, I sure do wish I had known all of that when I first started looking.
Edit:
Is G~A~S~S~E~R a filtered word for some reason?