A: There are no citizenship or residency requirements for selling internationally via Amazon, eBay and most other web marketplaces.
This is a great time for companies such as yours that are expanding their international reach. I believe seamless global eCommerce will be the next big wave in online retail. There is a lot of very good software that makes it easy and convenient for online merchants to list products globally. For example, I recommend MerchantRun (www.merchantrun.com) for international eBay sellers. MerchantRun allows you to list your products on 21 global eBay sites through a single user interface. If you're looking for alternatives to Amazon and eBay, then you may want to consider selling on Bonanza or Facebook.
Of course, selling your products is only part of the international eCommerce challenge. The other piece of the equation is getting your products into the hands of your international customers. You can do this through FedEx, UPS or the USPS, but the shipping costs are pretty high. If you have a fairly large volume — a few hundred shipments per day — then you might be better off outsourcing your order fulfillment to a fulfillment company that is experienced in shipping to your target countries. This can reduce your shipping costs and accelerate delivery times, giving you a competitive advantage as you try to attract more international customers.