Amazon book alerts
Of great use to newsrooms. The online bookseller notifies readers when books are published on subjects they're interested in, or by their favorite authors, or even with certain words in the title. Especially useful because the alerts come well before the books are published. (Registration required.)

Arts Wire
Weekly updates on arts: politics, conferences, events, funding, jobs, Web sites. From the New York Foundation for the Arts.

PollStar
Are you dying to know when your favorite music group is coming to town? PollStar will send you an E-mail whenever their tour schedule is updated. You can register for an unlimited number of artists. Or search the site by artist.

Publishers Weekly
A daily service for booksellers (and readers). "Aims to give booksellers the most up-to-date information on books that are receiving media and review attention, news stories about independent and chain booksellers, and changes in publisher policies that will impact booksellers."