Note: This is a basic apple cider instructable. For more ideas, see Hot Ginger-Spiced Apple Cider by ewilhelm or Home Brew Hard Cider from Scratch by actsofsubterfuge.
Step 1: Apple Cider vs. Apple Juice
"(1) There is no difference at all. (Source: large midwestern bottler.) Uncle Sam confirms that there is no legal distinction. In other words, it is all marketing booshwa. But see below."
"(2) The store-bought stuff is juice, the homemade stuff is cider. (Source: East Coast conglomerate; also, the old edition of the Encyclopaedia Britannica.) The product you buy from roadside stands usually has not been pasteurized. Consequently, it ferments over time, giving it a mildly alcoholic kick. What you buy in the store, in contrast, is pasteurized soon after crushing, preventing fermentation and resulting in a pleasant but kickless taste. The manufacturers call their product cider in the fall for marketing purposes."
"(3) Cider is made from apples that are picked early. (Source: Washington State outfit that claims to be the country's largest maker of juice and cider.) Early-harvest apples supposedly have higher acid and lower sugar content, producing a drink with a tangier taste. Thus true cider remains cider after processing because pasteurization doesn't affect the acid/sugar content. Therefore, the company claims, it's possible to make not only frozen cider concentrate, contrary to your assertion, but also "sludgy"--i.e., unfiltered, hence cloudy--apple juice. The guy I got all this from says his company is quite scrupulous about monitoring the acidity of its product and changing the labels accordingly."