In 1977 Winn joined his father's company, Winn Co., after graduating from the University of Southern California with business degrees in marketing and finance. There he worked as a manufacturer's representative.

In 1986, he founded and built a lighting company called Dynasty whch he brought public in 1990; it went bankrupt in 1993.

In 1996, he became a Dot.com entrepreneur when he founded Value America, an early sort of electronic mall that was briefly second only to Amazon.com. The company raised investments from Paul Allen and Frederick W. Smith, among others.

Valueamerica.com had a successful IPO in April 1999, starting at $23 per share, reaching up to $74.25 at its highest point. Winn's share of Value America was, on paper, worth over $1 billion after the company's IPO. By December 1999, Winn had resigned from the board after disagreeing with all but one of the rest of the board regarding restructuring. Value America filed for bankruptcy in August 2000, less than a year after its IPO. It was one of the first large dotcoms to fail.

Winn's book In the Company of Good and Evil: A True Story of Seduction and Betrayal is about his experience with Value America. Winn stated, "I, along with a small but great team of people, built a large and innovative retail company. But the founders turned the firm over to 'professionals' after taking it public in harmony with prevailing wisdom. They promptly ran it into the ground while lining their pockets. To cover their crime, they blamed it on me."

His first book is titled Tea With Terrorists, co-written with Ken Power. This is a novel that purports to document an investigation of the motives of terrorists. Winn has also authored Prophet of Doom, which is a survey of Muhammad's life as derived from the Qur'an and Hadith. Other works of his are In The Company of Good & Evil (also written with Ken Power), Future History and Yada Yahweh. He has published these books through the Cricketsong Books imprint, a division of Virginia Publishers.

According to Prophet of Doom and Tea With Terrorists, Islamic terrorists are inspired by the actions of Muhammad and the verses in the Qu'ran. Winn quotes extensively from the Qur'an and Hadith throughout his books.

He publishes a rendition of the verses of the Qur'an in Chronological order which was compiled by analyzing the material of Hadith.Winn worked with his team of researchers to compile a time line of Islamic terrorism.[4][5]

Regarding terrorism in Islam, Winn argues that the cause is "not Osama Bin-Laden, not Al-Qaeda, not some radical fringe group of extremists, but Islam itself."

Winn's work has been criticised. Muhammad Sultan of CAIR stated Winn "seems to lie in hatemongering and fomenting incitement for the purpose of cashing in on fear and ignorance."

Winn claims to have documented attempts of "Muslims filing complaints with the domain registrar to release private information" regarding his location and their repeated attempts to hijack the site [6]. Some Muslims have circulated a petition to have one of his books banned and censored. Daniel Pipes claims that this anti democratic and violent response to Winn's books raises important concerns regarding freedom of speech and the press.