Tired of losing track of your PDFs? Why not build a document collection in Acrobat? The Collections feature in Acrobat's Organizer allows users to group PDFs arbitrarily, arranged by project, type of content, client, etc. PDF documents in a collection need not even be co-located -- if the desired PDF documents were stored in various places locally and on a network, they could be added to a collection without the need to move files around. Further, individual PDF files can be included in multiple collections, which is invaluable for popular reference documents.
Here's how to create a PDF document collection in Acrobat 7:
Open Adobe Acrobat 7.
Select File > Organizer > Collections > Create A New Collection.
Start your new collection by arranging your files from here.
OK, so you want to stamp your document. Maybe you need to give reviewers some advice about the document's status or sensitivity. This tip from author Ted Padova demonstrates how to add stamps with the Stamp Tool along with related comments.