Hello Million-ells,
You have to declare everything! According to this Link hidden: Login to view -
Never forget that you cannot hide from the IRS. While it is unlikely that they will come after you if you make $50 on selling your old motorbike, when it comes to importing or buying items with the intention of selling to make money, it's so important that you tell the IRS about your earnings.
So what software to use? Many are recommending Link hidden: Login to view as the ideal software to access and manage your ebay sales.
To help you get started I have found the following guides for you -
Link hidden: Login to view
Link hidden: Login to view
Hope this helps!