1. Read customer testimonials before you buy anything. People are more than pleased to complain about bad service online, so try to find sites and testimonials which are terrible so that you know what you're getting into. You should take bad reviews with a grain of salt, but if you see many, you know there exists a problem.
2. Make it a habit to register for price alerts. This goes even for purchases that you've recently made. Price alerts will let you know when a product has dropped to a price you like. And if you've recently purchased at full price, you can ask for a price adjustment to meet the new deal.
3. Before purchasing a product online, find out more about shipping. If you do not find any information about shipping costs, contact the vendor to find out if there are additional charges for shipping. If there are several shipping options, choose an affordable and reliable option to make sure you receive your product quickly.
4. Do not forget to comparison shop when you are looking for things online. People usually do that when shopping in physical stores, but they don't think about it on the web. If you choose the first sale you see, there exists a chance you will miss out on a much better deal somewhere else.
5. When you are searching for a spot to buy an item and none of the results appear to be from familiar retailers, you should be hesitant about entering your information. Look for security signs from Verisign or Cybertrust, so you know the retailer is not out to take your hard earned money.