I bought my 1009 in November of 2006 with about 50,000 miles on it. Here's a partial list of things I've replaced:
tires, thermostat, radiator, belts, hoses, glow plugs, glow plug relay, batteries, high pressure fuel pump, 3 starters, 2 starter relays, shocks
The biggest problem I had was with the starter. I finally got a good one from NAPA and the truck is great! I've been very pleased with it. My advice: take the time to find a good one and be prepared to bust a few knuckles. Get to know the people at your local auto parts stores. You can buy a lot of parts for these trucks from Advance, NAPA, and Auto Zone. Make sure you have towing coverage on your insurance or AAA in case you break down. AAA saved my bacon a couple times. These trucks are big enough for work but small enough to ride on a flatbed. Also, stay on this forum. The combined experience and expertise of everyone here will save you a lot of pain.
Have fun!