Contact / Source Maintenance
This window is really just a tickler file for you to keep information about any people, companies, comic book shops, mail order houses, etc. that you wish. This data is not used anywhere else in the application (though I will link it to the Source field on the Issue window in the next release - 5.1), so you can enter anything you like here.
I find this most useful for keeping track of names and addresses of people with whom I purchase and/or trade comics, mail order houses from which I order regularly, and Comic book shops with which I deal on a regular basis.