Business networking is an old idea. Social networking is a new one. But the two worlds are melding together rapidly on the internet, and businesses that don't have a presence on Facebook or Twitter risk getting left behind. Stephen Woessner, who helps businesspeople at the Small Business Development Center at UW-La Crosse has written a book on how to build trust and sales by using social networking. It's called "Viral Social Networking: How to Build Your Website Traffic and Online Sales." He talked with WPR's Terry Bell about his book.