As you sit in your chair reading this guide I can say with confidence that at least 20 things on your desk were made in China. This is because China produces everything from pens and USBs to the keyboard I am typing on right now! And everything that is made in China is at your disposal to buy! Whether you plan on using it for your personal use or to resell, China has what you need at prices you won't believe.
Pay with Paypal or Escrow. They are must safer payment methods when buying from overseas and offer protection. Most good suppliers will accept these payment methods. Once you have built a relationship with the supplier and trust them, then you can look at paying with Bank Transfers and other payment methods.
Compare several different suppliers. Find several different suppliers and compare them on prices, experience, knowledge and politeness. Suppliers who want to seal the deal right now and can't wait until tomorrow are usually suppliers you don't want to deal with. Don't be rushed into paying.
Build a good business relationship. Tell suppliers about your own business and what you hope to achieve. Make them want to do business with you. If they realise that you will be a returning business customer, you will be more likely to strike a better deal.
Confirm business information. Try to find out as much as you can about the seller and their business. You can then confirm what they say (search it on Google) to make sure they aren't lying.
Find out where from China you are buying from. Shenzen is one of the safest places you can buy products from, because that is where 70% of products are sold from. Find out where your supplier is selling from and research the area and its reputation.
Check the grade of product you are buying. In China, most products are given a grade of A, B, C or lower. A is the highest quality product you can buy and anything after is of lower quality. If you plan on reselling products, you will most likely want to buy grade A products. It will cost you more, but it is definitely worth the extra money. Just tell the supplier that you would like Grade A quality and don't mind paying extra for it.
Take your time in searching. Finding the right supplier won't always be easy. It can sometimes take a while to find the right supplier. Earlier this year I was looking for a packaging supplier. It took me four months and countless inquiries until I finally found the right one, but it was worth the effort. Chances are it won't take you that long to find the right supplier, but don't expect the perfect supplier to be the first one you talk to.