I am reproducing some of my Answers which I have answered in the Microsoft Sharepoint Forum.
These Blogs are in the Q & A Format and I have edited some of the Questions and Answers for the sake of clarity. However, I Acknowledge & give Due credit to the Respective Questions Posters and Answerer.
Q) we have many site with 3-4 Document Libraries Is it possible to create a view that show contents from all these Document Libraries?
A) You can use Dataview Webpart in case you have only WSS 3.0 but not MOSS & Content Query web-part (is available only in MOSS).
How To CQWP -http://office.microsoft.com/en-us/sharepointdesigner/HA101741341033.aspx