Hi Michael
I have found a Ruby script for import OBJ file format in Sketchup :)
http://www.crai.archi.fr/RubyLibraryDepot/Ruby/RUBY_Library_Depot.htm

Not yet tested but... suspense If it's works that's a true gem :):)
You must have this progressBar.rb
and the principal script : Objloader.rb
All is free and must put into the folder Plugins of GoogleSketchup http://sketchup.google.com/

I will test that :)

oups don't more exist :(