Some 'repaint kits' as we often call our templates are available at the simv. There are kits for many of the default aircraft (including default 737) and a few others.

http://www.simviation.com/fs_paintkits1.htm

As for the 737 Experience, I think I read somewhere that the kit is included in the zip file. (Just cheked and this is true of the V1.2 at least. I expect its true of the erlier versions too)

Hope this helps, any more questions just ask.  8)