@GamingCampaign -- no you do not need anything special. The logic is as follows --- the content you create is your and has nothing to do with USA. It is no different than a visitor that comes to USA, visits the Grand Canyon and after going home uses the photo on Calendars and thereby makes money. Unless the sales come fro the US, the income is not US sourced, never mind the "work" -- the taking of the photo was done in the USA -- it is personal at that time. So to me your work, whether posted right away or later has nothing to do with "work" for somebody in the USA and thus not connected/ sourced in the USA. On the other hand, if you worked for Siemens , say and came to the USA to install equipment and train the users for a month, that earning can be construed as connected /sourced to USA, possibly.
So enjoy the USA, hope you come back again.
