Consolidation/ combining identical and non identical data

Hello Everyone
Can anyone guide me in the right direction...?? Please!?!?

I have given two data sets-one from November 2010 and one from November 2011.
My problem is that some of the SKU's were sold in 2010 but not in 2011 and reverse and some SKU's were sold both years. I need to combine the data for a report.

My outcome should be a comparison of each SKU compared between 2010 and 2011 with its associated sales price. There should not be any duplicates of products of course.

The attachment includes: Sheet one is data for November 2010
Sheet two is data for November 2011
Sheet three is what it should look like once it is done.

I did sheet# three manually since I have no idea how to combine them. Any help or guidance would be appreciated.

Thanks so much in advance!

Tocessa