Yeah, i think from an SEO point of view the .net would be better unless the extra word is very much related to the celeb, EG David-Beckham-Football.Com but im not sure.
Thanks, the celebs name is searched over 100k times a month according to overture and as I don't mind using hyphens for sites I am gonna develop I think it could do ok.
I think .net with a single hyphen would be much better. In case of celeb-name-extraword.com the potential of that name would be determined by that extraword.