You can shell out nearly 30 bucks for Free: The Future of a Radical Price by Chris Anderson, editor in chief of Wired magazine and author of The Long Tail, or you can download the audiobook for free from publisher Hyperion’s website or at LongTail.com. It’s available on Scribd, Google Books, Shortcovers and iTunes. All free, for varying lengths of time.

At the Hyperion site, you’ll need to provide your e-mail address so it can send you information about its “other great books.” The hope is that by giving you Free free, you’ll become a paying customer for upcoming books.

Anderson skillfully makes the case that free is a business strategy here to stay and that increasingly, businesses will profit more from giving things away than by charging for them. “This new form of Free is based on the economics of bits, not atoms. It is a unique quality of the digital age that once something becomes software, it inevitably becomes free — in cost, certainly, and often in price.”

In Free, he explores the evolution of the free economy, its various forms, how it works in industries from software to publishing to retailing, and where it’s headed. He persistently drills home the point that “free” isn’t just a marketing gimmick, such as the age-old game of offering free samples to lure in consumers.

Anderson kicks off his book with a dollop of free-marketing history — the tale of jiggly Jell-O gelatin. Invented in the late 1800s, it was “too foreign a food and too unknown a brand for turn-of-the-century consumers.”

Another reference from the past is “free lunch,” which sprang up in the 1870s as saloon owners began offering free food to customers who purchased one drink. The bet: They would buy more than one drink and fill the saloon during a less busy time of the day, Anderson explains.

Today, free has taken on a contemporary form, but its essence is much the same. For many businesses, it makes solid sense to give away digital bits such as basic software or an online book, so they can charge for add-on and bonus features or advertising that comes with it. Some examples:

•Google. “Most of us depend on one or more Google search services every day, but they never show up on our credit card,” he writes. How can they do that? Google makes its dough from “search results and ads that other sites place on their own pages, sharing the revenues with Google.”

•Webkinz. These stuffed animals cost money, usually under $20. Typically, kids receive them as gifts, go online for free and play with digital versions of their toys.

•Music. Musicians such as Radiohead give away their music online instead of worrying about pirating. Free lets them reach more people and create more fans, some of whom attend their concerts and even pay for premium versions of the music, Anderson explains. Radiohead’s In The Rainbows album, its seventh, was available for what you wanted to pay for it online. It became the group’s most successful album to date. Average price paid: $6. The tour that followed the release was its biggest ever, selling 1.2 million tickets.

“Free is not new, but it is changing,” Anderson writes. The emergence of a free digital economy from software to books, music and even used goods is having a transformative power in today’s marketplace.

The spoils will go to those who grasp what’s happening and accept it as a challenging puzzle to be solved. They will be the ones who build a business model that can exploit the free economy by pairing paid-for extras with gratis underpinnings.

Anderson delves into the psychology of free. From a consumer’s perspective, there is a huge difference between cheap and free, he explains. Zero is one market. Any other price, another.

Bottom line: “Giving away what you do will not make you rich by itself. You have to think creatively about how to convert the reputation and attention you can get from free into cash. Every person and every project will require a different answer to that challenge.”

Now, about that free shipping …

“Free: The Future of a Radical Price” by Chris Anderson; Hyperion, 274 pages, $26.99.