Websites such as Amazon have long been favourites for shoppers keen to save money but as commercial sites aimed at domestic users have proliferated, so too have sites aimed at helping consumers navigate the maze of options.

Some of these help you research complex topics, some scour multiple sites for the best deals and some enable communities of frugal shoppers to share tips with like-minded consumers.

Research

Don't assume research sites are comprehensive, says Christopher Zinn, a spokesman for the consumer group Choice. He warns some sites earn a commission for finding potential customers and he advises consumers to check whether products are listed in order of merit or whether those that pay the site commissions feature first.

Utilities http://www.goswitch.com.au is among the oldest of a handful of utility comparison sites. Dig out your latest bill for gas or electricity then type in details such as your utility company, your postcode and the amount you paid. GoSwitch calculates how much you can expect to pay using other suppliers. The site compares six suppliers in NSW and 10 in Victoria. When we entered figures for a Melbourne home, GoSwitch showed our hypothetical consumer could save more than 20 per cent.

Financial products http://www.infochoice.com.au and http://www.cannex.com.au are long-established sites that compare financial products, such as term deposits, credit cards and mortgages. Up-to-date tables show how much you'll pay on mortgages and credit cards or earn on bank accounts or term deposits. As an example, rates on a six-month $50,000 term deposit in NSW range from 4.25 per cent at St George to 8.6 per cent at Elders Rural Bank.

Telecommunications The complexity of plans for phones and broadband make http://www.whistleout.com and http://www.phonechoice .com.au a blessing. The sites make their recommendations based on your estimates of how you'll use a mobile or the internet but they require you to know some of the terminology. Whistleout is the more intuitive of the two; PhoneChoice has a glossary to help you negotiate the jargon.

Catalogues These are a successful way for retailers to attract customers - and http://www.lasoo.com.au adds another dimension. It collects catalogues from more than 100 retailers such as Amcal, Myer, Lincraft and Toys R Us, although not every shop will have a catalogue available at any given time. Users can search for specials among retailers or browse. The results can also be filtered by suburb or postcode. It can be clunky to use but it's easier than wandering through the shops.

Shopping

Choice recommends you read a vendor's terms and conditions before spending your money and never reveal credit-card details unless the web address is secure. (The web address should begin "https" not "http".) Look for a returns policy, contact details, whether the stock is available and, when relevant, how much tax or shipping charges will add.

Flights Travel costs are soaring but airlines are trying to stay competitive. http://www.zuji.com.au has flights from 146 airlines and shows the taxes upfront. (Some competitors don't calculate the other fees until later, making it frustrating to compare fares.) Prices on international routes routinely vary by hundreds of dollars but pay attention: some flights take much longer than others, some fares are more flexible and amenities between carriers may vary.

Accommodation Not strictly Australian, http://www.hotelscombined.com still has the smarts to customise what it displays. Enter a destination and the site returns a list of options from a claimed 900,000 deals, 20,000 destinations and 195 countries. After you've selected a hotel, the site checks a range of websites and delivers a list of competing deals. At the time of writing, Melbourne's Vibe Carlton ranged from $139 to $182.

Retail http://www.shopbot.com.au limits its searches to Australian retailers selling computers, electrical goods and health and beauty products. When we looked, the price for the same Samsung microwave varied between $309 and $345. http://www.staticice.com.au does pretty much the same thing, except it specialises in computer and electrical goods. It claims to collect prices from 260 sources carrying nearly 900,000 products but its minimalist approach will suit people who know precisely what they want, not browsers.

Medicines Pharmacy Direct (www.pharmacydirect.com.au) is an online chemist operated by Coles that carries all the usual health and beauty products but its big attraction is medicines that are not on the Pharmaceutical Benefits Scheme. Original prescriptions must be mailed to Pharmacy Direct, although the website will take care of refills. Postage costs $5.95 for most orders but this is waived within Australia for PBS prescriptions. But if you buy a lot of medicines, be aware that online purchases can affect your eligibility for the PBS safety net.

Communities

Altruism is behind much of the energy that drives these sites but, as with any community, there are occasional problems. With coupons, it will become obvious if a deal is valid when you hand the coupon to a retailer or type in a promotional code. With cash-back offers, the delay between when you make a transaction and when you collect your rewards can be substantial.

Coupons OzBargain (www.ozbargain .com.au) started as the personal blog of Scott Yang in 2005 and has grown into a community of people who post discount coupons found online and in print. He says about 8000 people visit the site daily and, while the legitimacy of the postings is not checked, the community is quick to target dodgy material. The site has proved popular enough that some retailers, such as OfficeWorks, have posted to the site directly. The "freebies" and "forums" areas are great for tips.

Cash back Many websites offer money to sites that refer customers. MoneyBackCo (www.moneybackco.com) refunds those payments to its members by tracking purchases through web "cookies". Offers are available in just about every category from arts to travel. Membership is $10 but that is deducted from the refunds you earn. Founder Steve Ford says the site, launched early last year, has already refunded about $40,000 to its 1700 members. BankWest, Harris Technology and Lonely Planet are among its 981 merchants.