Researching a company's background / sales volume

[JoshuaPz]

I am looking to sell a generic luxury transportation-related domain I own and have pinned down what appear to be the two largest players the domain would suit. Both are based in the UK. Before approaching them, I'd like to fix an asking price on the domain based the companies' annual sales revenues, but I can't find an easy way to pull up this information. Neither company is listed on Manta, unfortunately.

Would anyone with experience in researching company background information care to offer some insight into these sorts of investigations?

 

[Keynes]

If they're not publicly traded, you'll be hard-pressed to find firm revenue figures. That being said, you can find information on the scale/size of the industry here:
http://www.statistics.gov.uk/Cci/nscl.asp?ID=5849

You might also want to consider valuing/pricing the domain based upon search volume and PPC costs, to back it into their opportunity cost (of advertising directly):
http://estibot.com