I had to do this. Actually, something much harder than this, because sometimes the "name" would be "Smith, John" or "Smith John" instead of "John Smith", or not a person's name at all but instead a name of a company. And it had to do it automatically with no opportunity for the user to correct it.
What I ended up doing was coming up with a finite list of patterns that the name could be in, like:
Last, First Middle-Initial
First Last
First Middle-Initial Last
Last, First Middle
First Middle Last
First Last
Throw in your Mr's, Jr's, there too. Let's say you end up with a dozen or so patterns.
My application had a dictionary of common first name, common last names (you can find these on the web), common titles, common suffixes (jr, sr, md) and using that would be able to make real good guesses about the patterns. I'm not that smart, my logic wasn't that fancy, and yet still, it wasn't that hard to create some logic that guessed right more than 99% of the time.
