Here are a few links to help you get started:

Notebook Software Guide Notebook 16.2 Software Activity Guide. Here are the instructions to easily create some fun, engaging lessons for your class.
Smart Logo This is the Smart Exchange where you can find lots of lessons created by other teachers. You need to register for it in order to download the lessons but go for it-it’s worth it!
Smart Logo Here is the training page from Smart for how to use the Smartboard.  There are some courses that you have to sign up for and pay but some of the free ones are great too!
  Glencoe Virtual Manipulatives. This site is great for Math grades K-8.  Has all manipulatives that you would need.
 Illuminations1  Illuminations Resources for Teaching Math. There are some fantastic interactive programs in here to enhance your Math lessons and some great Math games you can play on your Smartboard.
SMART Board Notebook Lessons Modern Chalkboard: Interactive Whiteboard Lessons.  Another great source of lessons to use with your Notebook software.