There are a LOT of 9/11 tributes that are being passed around (by now you've probably seen "Imagine" and "Proud to be an American" and a dozen others.)
A friend of mine put one together that contains images that I have not seen anywhere else ... includes shots of all three sites (even pittsburgh) and really focuses on the work of the emergency services and rescue/recovery personnel.
It's a little intense.
Now, the other warning... this thing is HUGE. (10 Meg). Unless you have a superfast connection (i.e., DSL, Cable Modem, or something), it will take forever to download.
It's a powerpoint presentation, but if you don't have powerpoint, don't despair. A copy of the viewer is provided at the website.
Faces of Heroes