Qatar does not have websites for most commerce. Best car to drive depends on what you want to do, only town, off road, racing (to AlKhor and back).

Prices are comparable to US cost. If you get a used car, be careful. Qataris are hard on cars. Try to find an Expat leaving town.

Lease for a month, learn to drive here in somebody elses car, see what you can find and then buy.