A brief overview of Freight Forwarders and their role in exporting. This information is taken from "A Basic Guide to Exporting" provided by the U.S. Commercial Service to assist U.S. companies in exporting.
Freight Forwarders and Shipping Companies

Freight forwarders help prepare export documentation, book transport for your products, and, if needed, arrange for customs clearance at the port of arrival. You are not required to have a freight forwarder, but they can be useful, especially if you are exporting for the first time, exporting to a new country, or prefer someone else to handle these formalities. Some of the big shipping companies, such as UPS, FedEx, and DHL, are themselves forwarders and customs brokers, offering account holders a more complete solution.

They also have websites with extensive information for exporters, including the documents required by each country they do business in. All three are strategic partners of the U.S. Commercial Service, whose partners now number over 100 and include a hotel chain, a major IT services provider, the professional association of freight forwarders and customs brokers, and many other types of companies that want to encourage customers to sell globally.