Old woodworking tools have become popular collectors' items, as have old hand tools in general. Planes, hammers, saws and unidentified "whatsits" can be found at garage sales, antique shows, and in old barns and workshops. There are hundreds of books, catalogues and online sites dedicated to the subject. ILearning a few tricks of the trade and knowing how to research woodworking tools will help you identify tools and provide a rich history of toolmaking.
Study the tool in question. Try to determine its function. You can easily identify the purpose of most tools. Saws, hammers and planes usually won't be confused with other tools, although some antique models, especially planes, are ornately appointed to the point of nonfunctionality. Collectors catalogue tools by the material with which they work---wood, metal or leather, for example. These categories are further divided by function, such as boring tools, cutting tools, and edging tools. Older tools also are heavier than modern versions, usually forged with cast iron.
Check the body of the tool, particularly metal parts, for engravings, patent numbers, logos or other stamp marks. Identifying the manufacturer is often the first step in verifying and categorising a tool, and patent searches have, in themselves, become a popular hobby. Planes, for example, enjoyed an enormous boom in the late 19th and early 20th centuries, with many more failed patented models than successful ones. Planes that sport unusual or expensive features, such as precious metal inlays or fine wood engraving, may indicate a custom-made tool; it may not be patented but may carry the toolmaker's signature. Don't forget to check areas other than the tool's body for identifying marks, such as the blade of a plane or saw.
Ask the seller of the tool in question about its history. If you find a tool at a garage sale, for instance, talk to the owner. He may be able to provide you with details, such as the fact that his grandfather bought the item in 1900 when he owned a woodworking shop.
Talk to experts in the field. Take your tool to antique shows or swap meets and ask questions. Experts love to share their knowledge. You also can post questions online at any number of antique tool forums and sites.
Research any identification marks you find on the tool. There are abundant resources to aid you. Some online sites are dedicated to manufacturers and categorised by the tools they produced, while others can help you find the manufacturer through trademarks and registration numbers. There also are numerous books available on the subject, so visit your local library. Many websites and books offer photographs you can use to compare with your tool.
Antique tool collecting has exploded in recent years. Hundreds of online sites are dedicated to the hobby, and prices for many collectable tools have skyrocketed.