I think that the cover of this book give a good indication of what you'll see inside. It's a list of 100 vaguely rude names of places and streets in the UK, each accompanied by a picture of a sign with the name on it and a couple of paragraphs of explanation. Not many of them are outright filthy, most are more suggestive or contain words that have rude connotations if you look at them that way (but that you might not think of as particularly rude in other circumstances).
This book delivers what it promises to do, but sadly just isn't very funny. It's a decent stocking filler or present for a friend, but not the sort of thing you'll come back to and read again and a again.