Entrepreneur--For manufacturers, wholesalers and retailers, shipping products quickly and reliably to clients and customers is a major concern. But transporting goods by ground, sea or air -- domestically or internationally -- can be a complicated operation for business owners who haven't explored every shipping method and the costs associated with them. Some of the most common mistakes include not knowing which shipping method to choose, being unclear about international shipping regulations and not double-checking shipments before they're sent, according to a USPS spokeswoman. Read more!