How are those various graphics put under the users name and where are they obtained?

Go to My RCU and then click Options. You'll see a thing at the bottom of the page that says "Change Avatar." You can upload a small image from your computer or (I think) link to one online. I don't remember the size restriction, but I think it's something like 72 x 72 pixels. If you have a picture you want to use and it's too big you'll have to use an image editor to resize it.