Before the advent of computers, the choice of fonts depended on the molds you or the typesetter had in stock. However, computers have changed the face of publishing by providing cheap access to a bewildering array of fonts. The sheer number of fonts can lead to a lot of confusion especially when two or more designers are working on the same project. The choice of fonts has to depend on a combination of legibility, readability and aesthetic beauty. The choice also depends on usage, whether the font is to be employed as a heading or display font or as body text.
Remember, fonts play an important role in establishing an identity of a title to its readers. Choose fonts carefully. It is advisable to pick a typeface that has all the versions (from ultra-light to extra-bold) and any special characters you may need.
You can buy fonts on CDs or, if creativity seeps in, create your own.