I signed up with
www.admob.com and have sorted out some adverts for mobile sites now, its a pretty good system and easy to use. There is a lot of interest from companies who bid on adverts, that go on your mobile site, and I was fairly impressed
The thing that was initially throwing me was changing the extension of the files to .php instead of .html (or .xhtml) so I could place their code within the pages, but it works perfectly.
