VB image recognition in a webbrowser-Controll

i need your help.

I would like to programm a software in VB, with this i can check if on a Website an image is somewhere and click there. The Website use flash.

So my intention was:

1. open the Website
2. make a screenshot of this site
3. check different pixels or in best case an small images.
4. click on this position

The Problems I found are:

• Browser.DrawToBitmap(.... => retruns a blank image
• i found no lib to check 2 images, if one is in the other

please help :)