Office 365 Overview

http://onlinehelp.microsoft.com/en-gb/Office365-smallbusinesses/ff637546.aspx

Outlook Web App videos -

http://help.outlook.com/en-us/beta/gg605090.aspx

Lync -

http://office.microsoft.com/client/helpcategory.aspx?CategoryID=CL102270108&lcid=1033&NS=COMM14&Version=14&CTT=4

SharePoint -

http://office.microsoft.com/en-us/sharepoint-online-small-business-help/introductory-videos-for-sharepoint-online-for-professionals-and-small-businesses-HA102604632.aspx?CTT=3