For quick reference, here are some sample URL formats that you can use. Please use them at your own risk, since their use may be restricted and thus possibly illegal for use with Maemo Mapper. I cannot be held responsible for anyone's use of these URL formats.

Google Maps (street)
http://mt.google.com/mt?n=404&v=w2.9...d&y=%d&zoom=%d

Google Maps (satellite)
http://kh.google.com/kh?n=404&v=99&t=%s

Virtual Earth (street)
http://r0.ortho.tiles.virtualearth.n.../r%0s.png?g=45

Virtual Earth (satellite)
http://a0.ortho.tiles.virtualearth.n...a%0s.jpeg?g=50

Virtual Earth (hybrid)
http://h0.ortho.tiles.virtualearth.n...h%0s.jpeg?g=50

Terraserver USA (WMS)
http://www.terraserver-usa.com/ogcma...PTIONS=INIMAGE
(Note: WMS URL formats requires the installation of proj.)

Edit: removed plain text to avoid crazy thread formatting. So now you can't see all of the WMS URL, but you shouldn't have to - just tap and hold the stylus on a URL and select "Copy URL" from the context-sensitive popup menu.