Buying type at the right price is a bit confusing for the beginner.
New type, available at very reasonable prices, is frequently described by its point size (a printer’s point is roughly 1/72 of an inch) and by the number of upper- and lower-case ‘A’s that the font (type package) contains. For instance, a 12-point font with 15 capital ‘A’s and 30 lower-case ‘a’s could be described as follows: 12pt 15A 30a. But don’t expect to find 30 ‘z’s; there will be proportionally fewer of those letters that occur less frequently in the language. See the Printer's Yellow Pages for sources.
Used type is frequently sold by the pound, especially if it is pied type (dumped into a container, unsorted). A few dollars should buy a couple of pounds, though type is getting harder to find and prices may therefore be rising. The experience of sorting pied type is great for those looking to master the lay of the case (that is, where each letter is stored in a typecase).
Be sure to examine the condition of the type faces when buying used type; if the edges of the letters themselves are dull or rounded, or if the face of the type has scratches or other signs of extensive use, the type will not yield a crisp impression. However, buying a few unpopular or well-used fonts at a good price, is perfect for the beginner because in the learning process, type is frequently damaged or crushed.
Rare type from older foundries is very collectible and can sell for hundreds of dollars a font depending on age, condition, and what a collector or user is willing to pay.