Instructions
Purchase from Master Replicas. Master Replicas (see Resources below) has produced dozens of variants of lightsabers that are authentic in almost every detail, durable, and reasonably-priced. Master Replicas even makes the much-coveted Force FX Lightsaber Construction Set, a modular lightsaber set with four versions of power cells, grips, pommels, and focus crystals and a "blade" that can be set to green, blue, or red with the flick of a switch. Many of these were carried by stores, including Radio Shack, but are now difficult to find. Still, there are other versions of lightsabers that are made by this company for sale at their website.
Purchase from online retailers. Some retailers, such as Think Geek (see Resources below) offer high-quality replicas at reasonable prices, including Master Replicas' Force FX lightsabers in a variety of styles and configurations. Most online stores have either a Frequently Asked Questions (FAQ) or customer service support or both which may answer some questions you have about the product. Stores such as these also have good buy-back policies and will likely refund your money if you're not satisfied with your purchase.
Buy the materials to make your own. Some websites, such as Obi-Wan's Jedi Academy (see Resources below) offer detailed instructions on how to build replicas of the lightsabers cobbled together for use in the movies. In addition to learning how to make a "real" lightsaber, you'll also be offered interesting glimpses into the world of cinema props.
Buy limited edition prop replicas. These are different from the other replicas mentioned above. These lightsabers are more expensive because they are limited edition craft works that are meant to hold an artistic value. Unlike the various Force FX replicas, there are no sounds or lighting effects and unlike one you build on your own, these are highly-polished, detailed collectibles faithful to the movie props. For more information, see Resources below.
Scan your local listings. Shopping channels, such as QVC (see Resources below) and HSN occasionally have special programs that feature either Star Wars collectibles or limited edition movie props. Check your local listings, or check their programming schedules online to see when these items are offered. The advantage with shopping this way is you get to see people interacting with the lightsaber including turning it on and off or handling it. This will give you some idea as to what you are buying, which is an advantage over online-only stores. One drawback, however, is that the programming is hit-and-miss and may not consistently offer lightsaber replicas. That being said, however, these channels often offer autographed replicas signed by movie stars or prop masters, which adds value to your collectible.