Hello and welcome to smogon =) u can get them all over the internet. Deviantart has lots of them but i can also make you one if u want. There are lots of people here who make them. Me and my friend Typhloterra.
http://browse.deviantart.com/?qh=§ion=&q=pokemon+avatars look here to see if theres the one u want. What one do u want? i can help anytime with anything =) merry christmas