Also I know how you feel about walkthrough, but at least give us list of the collectibles and their hints! There are 333 collectibles and I only managed to get 145 so far. Completing them t is gonna be a nightmare without the checklist.
Not that I want to force people to pay me, but there's a complete list of collectibles (as well as how to obtain them) in the behind-the-scenes book, which is available for $15. :)