READING ON THE GO; Audio books solve a multitude of problems for time-crunched book lovers.(ARTS & TRAVEL)

Byline: SUSAN L. RIFE susan.rife@heraldtribune.com

Books are hard to beat for portability and ease of use.

Even a pretty fat novel -- say John Irving's latest, "Until I Find You," at 818 pages -- still fits into a briefcase or shoulder tote. You open it, you read a few pages, or many, you dog-ear the page or slide a bookmark in, and when you pick it up again, you resume right where you left off. Can't remember who So-and-So is? Just flip back a few pages until you find what you're looking for.

But printed books aren't always practical. Propping a book on the steering wheel during your morning commute is ill-advised (although it has been done). Can't read while you do the housework or yard work. Hard to read on the treadmill, too. And employers frown on recreational reading at work.

Hence, the audio book. Instead of reading, you listen. In a variety of forms -- cassette, CD, digital and the about-to-be-launched self-playing digital audio book -- recorded books are changing publishing, and reading.

Although a relatively small number of titles now are available on audio, it's growing all the time. Bookstores and libraries stock books in CD sets; this fall a new form, called a self-playing digital audio book, will be available. Online retailers sell digital versions of everything from best-sellers to archival speeches and audio versions of newspapers and magazines. You can study a …