The Guide to 100% Completion and Quick Collectibles Guides are under construction.
I hope to have them finished soon. If you're still missing some collectibles I would suggest checking the annotated level maps linked from each section of the walkthrough. If you still can't find what you need, try posting on the Lara Croft Online forums. I check in regularly to answer questions and share info. You're also welcome to contact me directly.
Thanks for your patience and happy raiding! :D