In most Western cultures we're used to paying the ticketed price on goods. But in many countries bargaining is standard practice and you'll save a packet if you learn how to do it properly.
When you have to ask the price of something in a shop, there's a good chance that the price is at the shop keeper's discretion. Don't pay the first price that's offered.
To get an idea of how much something is worth, ask fellow travellers. But be careful if you are asking people you don't know well: most people will tell you they scored a bigger bargain than they really did! Shop around. If you're not a regular haggler, check out prices at different shops to get a feel for the common starting price.
There is nothing worse than hitting on a huge bargain, only to discover you had the exchange rate wrong and have paid a fortune for your purchase. Write down a list of key exchange rates: the value of $1, $10, $50 and $100; and keep it handy so you can check it during your negotiations.
If you're buying furniture or carpets, make sure you find out about shipping costs before you settle on a price and find your budget blown by postage charges. Also remember that the Australian customs service might charge you duty on new goods. Make your own enquiries: don't rely on the assurances of the shopkeeper.
Haggling is a business negotiation, not an argument. If you can't strike on a deal you're both happy with, bid a friendly goodbye and leave.
Many experienced shopkeepers will ask you what you're willing to pay for something and you'll find yourself sucked into a negotiation before you know it. Don't waste your time and energy on bargaining unless you really want to buy the item.
Shop keepers in many countries are used to dealing with Western tourists and are going to be a lot better at bargaining than you are. If you seem uncertain or vulnerable, you're probably going to get fleeced. If you have a buddy to discuss things with, you will find bargaining a little easier. Single female travellers should be especially careful to go shopping with a friend, as they are often targeted by vendors.
You'll often drive a better bargain if you buy a range of things from the same seller and negotiate a bundled price.
There's no point in bagging a bargain for an animal hide drum only to have it confiscated at the airport on the way home.
Treat haggling as part of the experience. Smile and have some fun ... you'll find it'll make for a better deal too.