SO...This is what I ended up doing:

In order to get all of the names separated, I split them into columns and sorted A-Z started with the right-most column. Highlighted everything but the last name, deleted and allowed cells to shift to the left. This took a while but then I had my column of last names and it was much easier to use the methods described.

Thanks guys for talking me though this. This was one of those cases where there just wasn't a simple fix.