Information on carvans - a good source of pricing information

I'm looking into buying a 2nd hand carvan ( golf, focus or Astra ) from the North. There doesn't seem to be many listed on websites like autotrader.co.uk. Are there any websites or publications that would be a good source of pricing information or is the best approach to call some Ford, VW dealers.

Thanks in advance.

Look in the "buy and sell" newspaper or its northern equivalent.
Or the caravan magazines.
Or check out the "gumtree" website. london gumtree is the biggest but they cover dublin and belfast...on the gumtree website go to other cities and click belfast
hope that helps