Modern computers are typically well-equipped for publishers. Boosting memory and hard drive size are typically the only changes users need to make.
Publishers will want several peripherals, either attached to their computer or available on the network, including a PostScript printer for high-volume output, a low-cost ink-jet printer for basic color proofing, and a scanner for image capture as well as a fast Internet connection.
Font management software is a must for Mac and Windows users. Both Extensis Suitcase and DiamondSoft Font Reserve can do the job. On Windows, Adobe Type Manager also fits the need.