Does Christmas really cost less in cyberspace?

Do you fancy handing over your Christmas shopping to an internet search tool?

No traipsing around stores getting hot and bothered during the next seven weeks' build-up to Christmas. No pressure to shop before closing time, no waiting for a bus to get home - and, best of all, no crowds.

All you need do is switch on your computer and log on to a "shopbot" (short for shopping robot) website. Kelkoo.co.uk, pricerunner.co.uk and shopping.com (formerly Dealtime) are three of the UK's most popular shopbots, each able to search for any type of product you fancy.

Simply type in your choice of gift - the latest CD from Robbie Williams, say - and let the shopbot do the rest. It'll search thousands of retailers' websites and make a list comparing the lowest prices it can find. Click on the one you want, type in your credit card details and the online order is completed. All you have to do is wait for delivery, and give yourself an old-fashioned pat on the back.

If it sounds too easy, that's because it probably is. More people than ever before are expected to shop online for Christmas presents this year, to strike a bargain and take the hassle out of hunting. But using a shopbot may not deliver the best value every time.

The cheapest deals don't always get listed, and users can waste hours wading through pages of irrelevant searches. (Kelkoo, for example, has been criticised by the consumer body Which? for producing swaths of irrelevant results.) On top of that, the delivery costs can wipe out any savings you make - and you'll need to be vigilant against online card fraud.

None the less, these concerns haven't checked the growth of shopbots. Specialist sites have emerged, such as dvdpricecheck. co.uk and bookbrain.co.uk, offering DVDs and books respectively.

Since shopbots search across the internet, you should be prepared to grapple with a lot of - often useless - information if you want to unearth a bargain.

A quick test reveals the size of the task ahead of you.

A hunt conducted on kelkoo.co.uk last week for an Xbox 360 games console listed 4,383 results from 309 shops - but many of these were for accessories, not for the console itself.

Froogle - Google's shopping channel - listed 583 results for the same search term, and shopping.com just 89.

Using a shopbot does not guarantee you the cheapest prices. High-street stores are currently slashing prices in a bid to woo shoppers back, and can sometimes shame the web.

Bookbrain.co.uk quoted £6.74 including delivery for the bestseller The Insider, based on the diaries of the former Mirror editor Piers Morgan. But last week you could stroll into Books Etc on the high street and find it on offer for just £3.99.

Of course, shopping around on the high street involves a lot of time and effort. But sometimes waiting for a delivery may be more hassle than it's worth.

For example, you can pick up a 20GB iPod from Argos for £190, which will be quicker than ordering one from empiredirect.co.uk for £177. The latter delivers on weekdays between 8am and 6pm - no good if you are at work. If you want a Saturday delivery, you'll pay an extra £15.

Note, too, that commercial relationships between the shopbot and retailer can influence how far up the website's table a product price entry appears. Make sure you scroll through the first couple of pages to check that an item does not appear cheaper further down.

The shopbots make their money either by receiving a payment every time a shopper clicks through to an individual retailer's website, or as a percentage of the purchase made.

For the consumer, the size of the potential savings is determined by the type of product bought. Buying an MP3 player online results in an average saving of only 1 per cent compared with high-street stores. Hunt for a widescreen TV or digital camera, however, and a shopbot can help you save an average of 23 and 26 per cent respectively, according to Which?.

Despite this, the consumer body remains cautious about shopbots.

"Check what service is included, especially when buying large appliances," advises a Which? spokesman. "One company might install a new washing machine for free, or remove your old one for nothing, while others will charge you for doing this."

To stay safe online, look for a customer service number and postal address for any website you buy from, especially if you've never previously heard of the retailer. A quick phone call to confirm your order and check the delivery time can set your mind at rest.

And if you are buying a product for more than £100, remember to use a credit card, as this offers extra protection if the item is faulty.

When you are about to pay, look for "https" in front of the web address at the top of the page, and for a padlock or unbroken key symbol at the bottom.