Here is a quick Google Excel tip for you. How to remove duplicates in Google Spreadsheets.
Remove Duplicates in Google Spreadsheets
1.) Select the cell where you would like the de-duplicated info to begin
2.) Enter the function =UNIQUE(
3.) Select the cells you would like to pull data from
4.) Close the parentheses. Your function should look something like this:
Here is a video!
Via Google Guru.