First get the No CD thingy from this site.
It's in the CFS3 utilities section.
It saves wear and tear on your CD and some loading time
Essential must-have are the NEK country files which expand the list of your available countries.
Many aircraft such as the 1% planes depend on it.
It's a massive download split into a dozen files.
Right out of my head I think you need only three of them to make the basics work.
I'd suggest get the latest file, check the readme and then get the missing essentials.
http://www.simviation.com/cfs3_misc4.htm.
1% aircraft here:
http://www.avhistory.org/More aircraft here:
http://www.groundcrewdesign.com/http://www.geocities.com/cacforcfs3/For terrain mods go to
http://www.sim-outhouse.com/index.php?page=main&loc=pagesCheck the CFS3 ressources link to the right side ,
make your way to CFS3 scenery and get yourself Winding Man's Scenery Project. Rev 4.6 plus an update is the current version.
On the same page check Ruff Dawg's 256cfs3 tweaks, helps greatly to improve terrain texture detail (get rid of the blurry terrain ring)
Effects, again Sim-Outhouse, look out for fox's effects.
Watch out for this anytime this year.
It's a massive freeware addon to CFS3, actually a standalone installation based on the core CFS.
http://www.medairwar.com/