As celebrity go, fans can own celebrity domains as long as it is a true "fan site". Any attempt to make money by selling unauthorized merchandise, PPC, redirects, subscriptions, porn site, for sale page, etc... will more than likely mean your intent is to profit off of someone else's name, therefore, would be considered a cybersquatter and you would lose if action is taken against you.
If you have a celebrity domain, I reccomend doing the following....
Have content about the celebrity on the site
Make sure you state it is an unauthorized site
Update the site every so often
Never make money off of it
Never initiate a sale of the domain to the celebrity
If possible, do not use your normal whois lisitng for the domain. Create an account and make it seem amatuerish, but with correct information. If someone decides to pull up all the domain you own through whois, they could say "he is a squatter, look at all the domains he owns and is trying to sell for profit. His fan site is only a way to try to ectort money from my client"
If you are looking to sell the site, never state it openly. If you receive a letter (or email), always state you have no interest in selling the domain and state you are a fan of that person. Letters can come from "bigwigs" but disguise themselves and a regualar person.
Another way to make money by selling it (even though i have not done this yet, so it is only a theory). Sell the site as a whole and always make it seem like you just want to be compensated for the work you put into a site, not for the name. I don't know if I would try this or not.
I have succesfully kept several "fan sites" up after being contacted many times by lawyers, agents and financial consultants. I was never confrontational, but I didn't back down from the threats. My best "fan site" is a person who is known as one of the greatest in history in his sport and every knows him. I was contacted many times, but they backed off kowing that I did nothing wrong and they had no case.
If you are ppresented with an offer you can live with, always, always make it seem like you don't want to, never jump at the first offer, make it a little tough because "he is your favorite player/singer/etc" and don't really want to part with it. Never try to get too greedy, let them make the offers, never counteroffer, if they insist that you counteroffer, always state the amount of time you put into the site, praise the person profusely, let them know how much it will "hurt" is you give up the site.
I am not a lawyer and this is not legal advice, but I have successfully defended several of my fan sites doing the above listed techniques.