I am also having same requirement to add content(pdf,Excel etc.)search in folder metadata and associate with the folder. Please update me if anyone having any idea to implement this, I am new to Alfresco development and very alone no alfresco person to help me out here. Thanks in advance - Nandkishore
Create an aspect with properties for you metadata. Add the aspect and set the properties. You can write your own java script actions, wire up behaviour or use a meta data extraction, … All of which you should be able to find on the wiki.