You can do that on our site! Here is the URL for the user upload area (the last tab on the right in the Downloads section)
http://phrogram.com/files/22/default.aspx
As for taking what you have created, packaging it into an executable and trying to sell it - - well, that is a fair bit more complex. On that topic, check out this thread -
http://phrogram.com/forums/thread/6232.aspx