Cgyguy - I'm also in Calgary and thinking about shipping over my 4 year old GMC Acadia. My only worry would be if it's properly equipped to handle weather conditions in the Middle East. With the limited driving that we'll be doing over there the thought of selling a perfectly suitable vehicle here and picking up something over there is a bit discouing. Paying the premium to ship our vehicle over may be worthwhile. Please keep me posted on what you're thinking.
O&GEngg - there are actually several places to look for used cars (online forums, newspapers, and the Aramco classifieds (which can only be accessed after you come here). The market moves pretty fast, so the list above is outdated but still representative. I don't know what you would be able to do with an up-to-date list, since you'd be foolish to start a transaction sight unseen before you come, and we can't publish the phone numbers or email addresses of the sellers in the forum without their permission anyway.
In my humble opinion, you would be better to have some patience and plan to start looking for a car after you get here. Rental cars are a bit of a pain, but can serve you fine until you find the right car from the right person at the right price (I rented for two months before buying an end-of-the-year new car, then bought a second used car from someone retiring from the camp six months later).
I came about 3wks ago from cowtown with just two suitcases. In my search for a vehicle here, I have come to the conclusion that a new GMC Suburban, Yukon or other SUV is the same price (and sometimes less) here as compared to Calgary. So paying to ship, is not making sense for me.
Other brands are more popular and command a higher price.
There is a lot of used vehicles for sale outside the camps, but they don't drop in price as much as you would like, so buying new with no worries is worth the small incremental cost over a used one.