any recommendations for a minimal content management and wiki PHP solution?

The wiki bit is pretty easy though it could also be included into the overall CMS or similar solution. I need to setup a website that will host a number of PDF or similar business related documents. I then need users to be able to search the collection of documents returning only the relevent files for download.

I'd prefer to avoid an overkill solution like Wordpress or my Plan D which is writting my own basic PHP with MySQL back end. Any recommendations on what I should look into or where I can find PHP examples for a basic folder/file scanner (into MySQL database) and search field?