From my webcast today - here are the links - be sure to search using the tags 'MOSS' and 'SharePoint' on my blog for even more information!

Link to Developer Introduction to Workflows for Windows SharePoint Services 3.0 and SharePoint Server 2007

downloads for development environment

WF templates for VS

WSS 3.0 SDK

Sharepoint 3.0 SDK

other resources

Nick Swan's Blog re-workflow in MOSS

Paul Andrew's Blog - workflow general

Eilene Hao's webcast - workflow development in VS for MOSS