Flick through your newspaper or take a drive down the road and it can feel as if there are as many people and places selling cars as there are cars on the roads. Newspapers, television, the Internet, auctions, franchised dealers, specialist dealers, "supersites" - it seems everyone's at it.

The upshot is that venturing out to buy a car can feel a little like wandering into an Arab souk: everyone claims to be doing the best deal. If the seller is a dealer he may be offering you a mechanical warranty, cheap finance, or favourable part-exchange terms. If he's a private seller he may be offering you the lowest price possible but no guarantees. If you visit a supersite stocking hundreds of nearly new cars, it may boast low prices but offer you equally little money for your old car. And those are just the good guys...

As in all walks of life, the world of car selling attracts its fair share of rotten apples - crooks such as "clockers" (fraudsters who wind back odometers so they show a lower, more attractive mileage) and ringers (thieves who give stolen cars a false identity). And then there are the people who fabricate service histories, make one car from two halves or resell cars that are still on finance.

Small wonder people believe buying a car is as stressful as moving house. Which is why, to help them - and you - we've compiled a guide to the seven most popular sources of new and used cars. Click the links below and we will cut through the sales pitch to tell you precisely what each can offer, as well as summarising its unique advantages and disadvantages. As they say, knowledge is power and when it comes to buying a car, you can't have too much of either.

• Franchised Dealer
• Independent Used Car Dealer
• Classified Adverts
• The Internet
• Supersite or Car Supermarket
• Auctions
• "Scratch" Dealers