Thanks guys, I thought it was canonpricewatch but I just could not find any graphs. Now with your help I know to look for the product, click on it and then the graph is all the way down at the bottom.
If I was in charge of the website I would definitely add a more prominent link maybe even the option to show a few graphs of different products on the same page.
Anyway, I am happy to have finally found it. I did discover pixel-peeper.com on my journey through Google but I am not sure how accurate their graphs are.