PRACTICAL VIEW / ABOUT YOUR PHONE BOOK : The 411 on Your Directory

* The Product: The phone book. It’s more popular than Judith Krantz and Danielle Steel combined but, let’s face it, you aren’t going to stay up nights to see how it ends. Things might change, though, because the phone book has tried to transform itself--as if it were a Krantz heroine. No longer just a big book of numbers, directories include a wide range of consumer information and have sparked a boom business of their own. The Yellow Pages Publishers Assn. reports that approximately 140 members published 6,200 directory titles last year in a $9.2-billion industry.

* Vital Statistics: In California, there are about 20 million Pac Bell phone books in circulation; GTE has about 4 million and independent publishers (Donnelly is the largest), about 5 million.

Phone books are delivered every day of the year, except Sundays and holidays.

In Los Angeles County, about 500 people a minute look up something in the Yellow Pages, which has 2,000 plus pages.

What gets looked up the most? Pac Bell reports restaurants (16.6 million references a year); airlines (10.4 million); pizza (9.5 million); department stores (7.2 million); auto repair and service (6 million). Dentists, plumbers and exterminators also rank high.

* Upside: Additional books are free in your service area.

* Downside: Other directories will cost you. The general rule: the closer the area, the cheaper the book. Neighboring directories can be had for less than $10 each. Books for Manhattan and Chicago--popular requests among Angelenos, cost $37.50. (The 800-number for ordering is in your phone book.)

* What’s More: Phone book consumer sections have grown in size and scope. Pacific Bell’s white pages opens with a 100-page directory that includes a first-aid section with Poison Control Center information and a five-page earthquake survival guide that is printed in five languages.

In the Greater Los Angeles yellow pages, theater seating plans and voter registration details are among the 50 or so service pages before you reach the listings.

* Turnover: In one year’s time, about 30% of the demographics in L.A. change. People move, get new numbers, ask to be unlisted. So the phone companies say new books need to be delivered every year.

* EcoFactor: Environmentalists say too many books are bad for the chopped-down trees and for the ever-filling landfills.

* Dial 411: About 40% of callers rely on Directory Assistance for numbers. Although operators boast of finding a listing in 22 seconds, they get slowed down by such requests as “How deep do you bury a dog?” or “How do you bake a potato?” Of the latter, the operator reports: “It was faster for me to tell her ‘One hour at 350 degrees’ than to explain that we don’t give information.”

* Up and Coming: Computerized yellow pages, portable computers with internal cellular telephones, laser disks and CD ROMS. The new buzzword: personal digital assistant.

And in New York, the Nynex Corp. has combined 300 phone books onto one CD.

* All’s Well. . . : “The day will come when the telephone book--an actual physical book you can break a window with--is no longer our best resource,” says GTE’s Dan Smith. “But for now, it’s the easiest way to get the most information the quickest.”