This wouldn't have been a big deal if everyone had ignored the guy. So some bigot wants to burn a book, let him; just ignore him. The fact that everyone is giving him so much attention is causing way more problems then the actions he is doing.
If you want to have fun with him, you should bring your bible's and crosses to the burning and join in on the anti religion fun. Bring a Book of Mormon and some L Ron Hubbard to the event too. Hell, bring an American Flag and the Origin of Species as well just to make sure all your bases are covered.
People should be allowed to burn stuff in protest of things they believe are wrong. They have that right. It doesn't mean it is good or appropriate. The fear that it will be used as a recruitment tool or upset other people is not a valid reason to stop them from protesting. If anything it is a reason to allow them to protest. When did we loose our spine. I will not cower to extremists of any religion, not the Bible thumping abortionist killing kind nor the suicidal Islamic kind.
Let the man burn his books and live his hate filled life, just ignore him and his 50 congregants. There are 310 million other people in this country who disagree with what he is doing, if one person burning copies of the Qur'an can cause so much harm and the Extremists can't look at the rest of the nation that is appalled by his action, then maybe he is right to do so after all.