While you are allowed to create a thread specifically for requests, you need to outline what you want in your request.
However, if you look through the threads in the section there are some that are marked with "Shop" on them. You will most likely have better luck going through those threads and following their forums for requests.
Unfortunatly, due to the April Fool's Prank today, I don't belive these current threads are showing their prefixes. Please follow this link to be able to switch to a theme where prefixes are tagged.
http://www.pokecommunity.com/index.php?styleid=48