Exactly as previously posted. No different than a reg'd TM name. If a fresh reg contact your registrar and request a refund/credit. If not, delete the name and stay clear of celebrity names, band names, TMs and the like. Good luck.
Not really, as you aren't allowed to make money from a celebrities name in the same way as a trademark, so although you might be able to setup a fan site without any major issues, you start to hit dodgy ground if you try and advertise on the site or sell the site.
Big names or estates of big names, are more likely to actively pursue people making money from their name.