Geting images from site using Gecko in C++

Hello,
I am creating small app for geting all images from site provided with
URL. So far I did wrote a working app, but it parse HTML myself to get
all images put on site with <img> tag. There might be some images
added with CSS or JS. Someone told me "use" Gecko.
Is there anyone who could send me some examples on how to obtain info
of images on site using Gecko in C++? As for now I'm writing it for
Windows, but I want use Gecko because it is cross-platform and fast.

Thanks for any help, links, tutorial. Anything which will help me.

Janusz Paszynski