!!!!!!PLEASE HELP ME!!!!!! I'm sure it's a simple solution...

!!!PLEASE HELP ME!!! I have a big excel file set up where each row
represents a specific city (this file is the "main file"). Then I have a
seperate excel file set up for each city. I enter data into the main file
and each cell feeds into the appropriate city excel file.
The problem I've run into is that the cities are listed alphabetically and
every month or so I need to add a new city (row) onto the main excel file -
when I do that all of the rows below where I added the new row are now
feeding into the wrong excel file.
EXAMPLE: If I have the following cities listed on the main excel file
Row 1 Austin
Row 2 Birmingham
Row 3 Columbus
And I have seperate excel files named Austin, Birmingham, and Columbus.
Austin excel file pulls data from row 1 of the main file, Birmingham file
pulls data from row 2 of the main file and Columbus pulls from row 3. If I
were to add Boston then it would change my main file to:
Row 1 Austin
Row 2 Birmingham
Row 3 Boston
Row 4 Columbus
Now the Columbus excel file that is pulling data from row 3 off the main
file is pulling the data for the city Boston instead of Columbus.
HOW CAN I FIX THIS?!?! PLEASE HELP ME!!!!