So, do you want a sims3pack file? A sims3pack file has all of the content included with the sim, with the exception of body sliders for create-a-sim. A .sim file does not have any included files with the sim. You would have to install them in your Mod/Package folder yourself. To install the .sim file, you put the in your Saved Sims folder.
Is this what you are talking about: :/