What are they, how do they look, where can i get them and how much? I thought the suspension does the job.

 

Spacers are adaptors for after market wheels with lug patterns that do not fit the stock vehicle lugs. They are generally a bad idea. I would just buy wheels that fit the stock lugs -

 

Spacers help when your wheels don't fit properly. Mabye the wheels are too wide for the car and you can use them to make the wheels stick out further. Also, some people use them just to fill in the fender so the wheels do look like they are recessed so far in. Using spacers can cause increased stress on your wheel bearings.

Generally, I believe they are a bad idea. If you do your research you can find a set of wheels that will fit your specific w/o using spacers.

Check this link and the pictures below for some visuals.

 

That's a pretty extreme version of a wheel spacer. The most common use for a spacer is to clear a caliper's protrusion. (distance out from the hub) Those spacers are ~.05-.25 inches and simply slip over factory wheel studs.