The US Geological Survey Homepage provides statistics and information about Helium, the 2007 Mineral Commodity Summary for helium is online there with informations about production, prices, trends, worldwide production and reserve base and more. It's definitely worth checking out for anyone in the lighter-than-air business.
-Minderal Commodity Summary - Helium (2007) [PDF]
The Mineral Commodity Summary is available from 1996 - 2007. There is also a Minerals Yearbook from 1994-2005, as well as one special publication.
Thanks to James Logajan from the AirshipList for finding this page.