If you're interested in banned books, visit the American Library Association's page highlighting "Banned Books Week" 2010, coming in October. http://tinyurl.com/yd55duu.
Of course, Samuel Johnson must have the final word on folks who hunt through dictionaries looking for the naughty bits. Though Henry Digby Best's account may be apocryphal, it's worth repeating:
Mrs. Digby told me that when she lived in London with her sister, Mrs. Brooke, they were every now and then honoured by the visits of Dr. Johnson. He called on them one day soon after the publication of his immortal dictionary. The two ladies paid him due compliments on the occasion. Amongst other topics of praise they very much commended the omission of all naughty words. 'What! my dears! then you have been looking for them?' said the moralist. The ladies, confused at being thus caught, dropped the subject of the dictionary.