Other
Association of Shareware Professionals
This resource is devoted to independent software developers and vendors with a primary focus on shareware products.
Wikimedia
Wikipedia: Shareware
Encyclopedia article that defines and gives a brief history of computer shareware. Also includes sections on implementations, logistics, criticism of the shareware concept, examples, and external links.
Other
The Pragmatist of Free Software: Linus Torvalds Interview
An interview with Linus Torvalds where he explains his views on "free software" vs. commercial vs. shareware.