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hand juicer
For the simplest juices this is all you will need. A small stainless steel manual juicer or a plastic one with a collection cup can be found for $15 or less. Combined with a good knife and cutting board, this tool will be all you need for the occasional juicing.
optional utensils
A citrus juicer is useful for quickly squeezing lemons and limes. A wheatgrass juicer is a hand-cranked extractor for recipes that use wheatgrass and other soft leaves. A mango corer is a useful tool for using fresh mangoes in your juices. Oxo makes one that sells at many grocery stores for around $12.
electric juice extractor
When you want to make juicing a part of your lifestyle or go on a juicing diet, you will have more success if you have an electric juicer. Breville, Black & Decker, Hamilton Beach, and Jack Lalanne are some of the most popular brands. Heavy duty juicers have a feed tube, much like a food processor, and a mesh strainer that separates the pulp from the juice. Most fruits can be inserted whole into the extractor, making juice preparation quick and easy. These units produce much more juice than a manual juicer, and the pulp can be composted or used in many recipes.
blender
A high-quality blender is a good addition because it allows you to expand your recipes to frozen fruit juices, smoothies, and blended soups. Black & Decker, Hamilton Beach, Cuisinart, KitchenAid, and Oster are the most common brands. Always buy a professional series blender with the highest wattage you can afford. You really only need two speeds and preferably a durable glass or polycarbonate bowl. Vitamix makes one of the best high performance blenders available. They cost more but last much longer than other brands, and they are so powerful that you can actually make a hot soup in just a few minutes. It is a good investment if you will be using your blender on a daily basis.