Thank you for your post.
If the main office was hosting the contacts file, the staff could connect remotely and add/edit the information and enroll a contact (or contacts) in a training course. FileMaker allows users to be on Windows and Macintosh computers at the same time. In the end, this would help everyone be up-to-date at all times, just in case a contact calls back and says something like "I just talked to 'X' and want to change my training course."
FileMaker Pro allows nine people to share the file simultaneously. If there are going to be more than nine people accessing the contacts database at one time, then FileMaker Server would be needed.
FileMaker Pro can also import several different file types. If the staff can attach a text file (comma-separated, tab-separated) to the email, the main office can then import the text file into the database.
I hope this helps.