The number of products that can be imported into or exported from the United States seems infinite. The key to success is to identify your niche or area of specialization. Most individuals starting an import/export business stand a better chance of succeeding if they specialize in a particular area instead of trying to make it as a generalist.
The more specific you can be about what you want to sell, the greater your odds of communicating clearly to your customers and making a sale.
Say you're interested in being an exporter, and you have a contact in another country. You call the contact and say one of the following. Which will give you better results?
"I'm the owner of ABC International, an export management company. If you tell me what you want, I can arrange to get it."
"I'm the owner of ABC International, an export management company that works with a variety of manufacturers of disposable medical supplies. If you're interested, I should be able to find products of interest for you."
The second statement is the one that'll help you reap the greatest rewards in the form of customers.