XML-RPC
- A Remote Procedure Calling protocol that works over the Internet. Specifications, API info, implementations, services, tutorials, service validator.
- http://www.xmlrpc.com/

Mycroft DeepDocs
- mozdev Project Mycroft's documentation for Mozilla-Search. Plug-ins bear a striking resemblance to Apple's Sherlock 2 code.
- http://mycroft.mozdev.org/deepdocs/quickstart.html

TCPMonitor
- A handy utility to observe REST, SOAP and XML-RPC traffic initiated by a channel. Part of the Axis Apache SOAP environment.
- http://ws.apache.org/axis/java/user-guide.html#tcpmon

Sherlock 3 Channel Development
- General information, guidelines, tips, and a development kit (SDK) for creating Sherlock 3 channels.
- http://developer.apple.com/macosx/sherlock/

Working with Web Services
- Apple Developer Connection's pages contain examples of working with SOAP and other web services.
- http://developer.apple.com/internet/webservices/

XMacL: XML for Mac users
- XML news and resource links for Macintosh users.
- http://xmacl.com

Sherlock-Talk Mailing List
- A list for discussion of Apple's Sherlock technology, especially all aspects of writing Sherlock Plug-ins.
- http://www.nisto.com/list/sherlock-talk.html

Sherlock 2
- Information on developing Sherlock 2 search plug-ins.
- http://developer.apple.com/macos/sherlock.html

The sherlock-channel-development Mailing List
- A developer-oriented discussion list.
- http://www.lists.apple.com/mailman/listinfo/sherlock-channel-development

Inside Mac OS X: Sherlock Channels
- Apple Developer Connection's Sherlock documentation.
- http://developer.apple.com/techpubs/macosx/AdditionalTechnologies/Sherlock/index.html