The The Eyre Affair by Jasper FForde on Amazon
here
It is light, witty and I laughed out loud. You can do character spotting from various well known books, as in this characters in books can be real.
The Times says:
'The reader is catapulted in and out of truth and imagination on a hectic, humorous and neatly constructed chase?
Then if you enjoy it, there are 4 (or5) Thursday Next books. Then also the Nursury Crime Series (where they investigate things like was Humpty Dumpty murdered or just drunk when he fell off the wall.