Although you don't seem to care about my opinion, here's a few more price baselines:
TTG shirt - I got an used one for $20.
Pins - Someone just recently sold both for $35. Their Max one seemed a little discolored...
Hero Team-Up Trading Card - I bought one for about $4 and another for $7.
Storyboard - I've never seen a drawing or cel from the show for sale before. That could be a good thing or a bad thing. Most cartoons (excluding the classics) go for $30-50. Too bad you don't have its corresponding cels...
Promo Sheet - No idea but I would think it would a pretty penny especially since it is signed...
Books - Although the paperback has a name, the beautiful art would definitely override it. Start that at $50. The other $100.
Have a massive amount of time to write about your favorite comic/videogame/cartoon?
BUT, if you do have a bit of spare time, why not spend it here: The Sam & Max Wiki
You'll be glad you did!