Malladine, every single portrait in my site falls into 2 categories. They are either taken from the IWD2 internal portraits or I've downloaded them from other sights.
HOWEVER... every single portrait on my site has been custom edited by me using Paint Shop Pro. Some pics are edited more heavily than others. Some pics have the colors of the clothing/armor changed. In others, I've changed the skin and/or hair color. I change background colors quite often. In some pics, I've totally deleted the background and replaced it with a totally different background. I'll often flip the image to give it a different look (i.e. the original pic has the person looking to the left, in my edit, the person looks to the right.)
As for how to get them into the game, read the FAQ page.
