So, how does one find stuff that's not intended for publication or wide distribution? If it's not cataloged in a library or in a database, where do we go? Google.
Search for "$MyIndustry white papers" and you'll get corporate documents,industry reports, etc.

Other good search terms are $MyIndustry +
- working papers
- working groups
- analysis
- patents
- report
- technical report
- industry report
- projections
- trends
You can also go do Google Advanced Search(http://www.google.com/advanced_search), and run this same search, but limit the results to PDF, and you'll get the acutal white papers.
