Millions of new internet addresses are put up for sale today, giving the public the chance to insert their entry into the world’s largest phone book.

The new “.tel” domain names go up for grabs this afternoon. Unlike other website addresses, however, they are not meant to act as catchy names for websites but rather to become people’s individual entries in a universal virtual directory.

Companies and individuals are being encouraged to list their phone numbers, websites, postal addresses, e-mail addresses and even their Facebook details in their .tel entry.

“.tel is your place on the internet, which will act like a switchboard.” said Kash Mahdavi, the chief executive of Telnic, the London-based company that runs the .tel registry. “You can say, ‘Here are my Facebook details, here is my mobile number, and people will always be able to find you’.”

As the new names will create the web’s repository for contact details, certain generic names such as restaurant.tel are considered to be particularly valuable given people’s internet search habits. However, the nature of the auction — the vast majority of the addresses will be sold on a first-come, first-served basis — means that a local, family-run bistro is just as likely as McDonald’s to secure the address for itself.

For the past new months .tel names that refer to a registered trademark have been up for sale in what is known as the “sunrise” phase of the sale. Some of the world’s most recognisable organisations and figures, from Microsoft to Ferrari, Bono to J. K. Rowling have already secured new .tel addresses. So far, more than 10,000 applications have been made to register new names.

Today, in the “landrush” part of the auction, all other names will be made available for purchase. Each costs about $300 (£210) for the first three years and $20 a year after that. They will become active at the end of this month.

The new addresses will become more valuable in coming years as the stripped-down web pages will be easily accessible through mobile phones such as the Apple iPhone and BlackBerry, so they could become the first port of call for people on the move.

The addresses could be a goldmine for those savvy enough to buy names under the noses of large companies that may want them at a later date.

Three years ago the BBC reportedly paid more than £200,000 for the bbc.com domain name. The most expensive domain name is sex.com, bought for an estimated $14 million in 2006 by the company Escom LLC. It is thought that the huge number of visitors that get directed to the site from search engines, such as Google, mean that the website is cost-effective.

Some concerns were raised that the new system was open to abuse. It was said to be possible to register a name while pretending to be someone else, and then leave bogus contact details — for example premium phone rate numbers. However, Telnic said that as .tel names focused entirely on contact information, it would be easy to validate quickly whether someone was who they said they were and then take action to remove them.

New domain names have lost some of their lustre since the glory days of the late 1990s, when speculators went on huge spending sprees in the belief that the finite number of names could only appreciate in value. Hopes for huge profits all but evaporated last year when the Internet Corporation for Assigned Names and Numbers, the body that regulates top-level domain names, announced that it would open up the system to allow any suffix.

The news rattled both domain name entrepreneurs and large companies, which are concerned that consumers will become confused by the infinite array of possible names.

Big numbers

185,497,213 number of websites in the world according to the January 2009 Netcraft Web Server Survey

51 billion estimated number of web pages in the world

$40m largest single e-commerce transaction (£25m), paid for a Gulfstream V private jet

£4.6m price paid for the domain name business.com in December 1999

4.2 billion number of numerical internet addresses

Sources: Netcraft, Boutell.com, Guinness World Records