I don't know how to get emoticons not on this site.
I google "free emoticons" of various kinds - vehicles, pirates --whatever I am looking for and see what I can find. This site has some fun ones.
Free Smilies: Angry - Forums Extreme.com - Smileys Emoticonss
Just right click on them and select copy image url and then paste it into the "insert image" link in the quick reply section.