Good place to start is the online training at office online
Sharepoint you’ll find there is a lot of information of technet too.
You might enjoy some of my sharepoint demos (or they may cure you of any insomnia issues).
Also check out some of the great books available. I'm personally really impressed with the recent crop of MS Press books. Our team is starting to do our Microsoft Certified Application Specialist exams - they aren't that hard to pass but really great for ensuring you have an end to end understanding of the products in Office. Even real experts here have all found they learnt useful new tips. The books we are using for that are the "plain and simple" series - continuing my quest for simplicity (see this rant about our recent offsite). these books are superb - easy to read and internalise.
They have a really cool preview tool that lets you preview the table of contents and index on amazon. Just think you could get a personalised signed certificate from Bill Gates like mine - he actually signs every one (that's a lie by the way). This Outlook certificate means I am now officially qualified to send email so watch out.