I think you are thinking of UV mapping. That’s kind of a preparation step for texturing. You can’t really model from that step. You can go into Photoshop and draw your bump map using your UV map.
I suggest you do a search online for Bump Mapping as it will give you a good idea of what it is.
As for the site, keep trying. It gets updated and tested often so it shouldn’t be down.
Good luck with your 3d learning journey.
Revanto 
