PO box is the way to go, and if you can get a PO box with fake credentials, even better.
Its not hard to buy a fake ID, and print up a fake utility bill, or mail with a fake name address.
As the consequences, most good feedback suppliers send a pack of 200 CD's no prob, unless they full boxes, 10-20 easily. There is a small chance customs will check it, but the most lazy of them all is your local post. (Never use UPS, FEDEX, or the big box companies) they live off of customs and broker fees, and you will get fucked.
As for your sellers, that's where you worry, make sure you have a tight game plan. I don't suggest ebay or paypal, you WILL eventually get reported, and have lawyers coming after you. (usually a cease and desist) make sure you have a good story where the illegal software came from. (Ive had my scare from Micro(penis)soft)
Best is deal software locally on Kijiji, or Craigslist or any other bst avenue. Use a throwaway phone to keep in touch with your customers, and change your phone every 1-2 weeks depending on your traffic. Also make sure you don't sell in YOUR city, if you drive , sell 30-40 min away from you, and never let them see your car by parking a few streets over, or in another plaza.
If you cant make $100+ with each of the software you sell, don't do it. Its not worth the risk for $20.