I haven't seen inside one. Do they make hot book bibles that are actual books/bibles that can be used, the same way a flame wallet can be just your regular wallet?

You can make one yourself

Let me elaborate.
Go to your local magic shop and purchase the flaming greeting card effect, I am not sure of the exact name but ask the dealer for it or perhaps they have a gimmick for a book.

Buy or acquire a bible from a hotel that is larger than the flaming greeting card

Glue the card in the front of the book with contact cement or permanent double stick tape

I make my own flaming bibles for my shows.

You can see it here a few seconds in.

http://youtu.be/pGRHXTY-ylc

A little late but I just got a hot book.
You can put any dustcover on it. Assuming of course it is close in size.
I had to trim my dust cover so it fits the book.
I went to a dollar store with my hot book and bought a similar size book with a dust cover.