While some of us are bequeathed pallets from some never-ending construction job on the roof or are lucky to have a career where pallets can be scavenged, finding pallets is not always easy for everyone.
Your best bet is to ask the manager of a local hardware, big box or grocery store if they have any pallets to spare. It's not foolproof, of course; some of them contract with companies that take the pallets. One thing we don't recommend? Just pinching them from the back of a business. Be kind -- ask first.
Some argue that pallets shouldn't be used at all because they're exposed to insects, rodents, weather, bacteria and so on. There's some good reason behind this argument. In 2009, a batch of Tylenol was recalled due to a foul odor that was linked to a chemical applied to the pallets used to ship the medication [source: Kavilanz]. But here's the deal: Bacteria is everywhere. Be reasonable about the pallets you use; wash them and inspect them. If you're nervous about potential harm, it's probably best to avoid interior projects and stick to using pallets on outdoor projects.
A word of warning: When working with recycled pallets, remember that they were designed to hold cargo, not cuddle people. You should always be aware that splinters, protruding nails and rough edges are par for the course. Sanding and smoothing can prevent a world of hurt.