There are many pedagogical and repository sites for IWBs but here are a few links that are extremely useful.

How to use a smartboard?
http://www.interactivewhiteboard.net.au/training/videos.aspx
This site includes links to training videos that are extremely useful.

Open License Viewer - http://www2.smarttech.com/st/en-US/Products/SMART+Board+software/NotebookIV.htm?WT.mc_id=schms_LAT_08

Pedagogy - who to use them with your class:
http://smartboards.typepad.com/

Repositories:

General Sites:
http://exchange.smarttech.com/index.html
http://www.scholastic.com/interactivewhiteboards/
http://www.whiteboardblog.co.uk/category/smartboard/

English

Maths

Science
http://ict-in-science-education.wikispaces.com/Smart+Boards (for Science Related Resources)