Geez... You guys make it look complicated. Why not just Text to Columns and delimit by commas? That would put the last names in one column and the first names in another. Edit and Replace all spaces with nothing, then do a quick join, if needed, readding the space like this: =B1&" "&A1 where B1 is the first name and A1 is the last.
To each his own, right? Just as long as it gets done.
1. I did not even know about Text to Columns. Thanks for pointing that out (for anyone who doesn't know, it's on the Data menu).
2. However, when I tried it I ran into problems with 3- or 4-name guys (e.g. Wily Mo Pena, Jorge De La Rosa). It's fine going from "Pujols, Albert" to "Albert Pujols", but it's a major hassle going back the other way. Given that I suppose I'll stick with my original method, since it works both ways.