The Whoniverse contains one reference guide that doesn't fall under other categories. It also contains a few standalone articles.
The TARDIS Technical Index
The TARDIS Technical Index is the most comprehensive guide to the workings of a TARDIS ever compiled. It includes facts from the TV series, the books, the audios, the comic strips, the spin-off material, and official reference books. Armed with this you're probably only a couple of steps away from creating a working model.