Buying at a discounter may shortcircuit needed support

Want a good deal on a computer? Some people would tell you to shop at a discounter like 47th Street Photo in New York or send a check to one of many mail order houses advertising in the computer magazines. Some of these places are shipping out famous-brand computers at just over cost - or discounting them 15 to 25 percent from retail prices at specialty computer stores.

But people who own computers, or consult others on how to buy them, don't think the discounts are so hot - especially for the person just beginning to shop around. With many of these places, if you need service or instruction, you can't get it. And if you did not buy the computer from an authorized dealer, he won't help you, either.

''Those people trying to shop the discount route usually do so at the expense of a guaranteed source of support for that equipment after it's purchased,'' warns Peter Weiglin, who used to be ''a perfectly harmless transportation consultant,'' but who now edits and publishes Apple Orchard, a magazine for Apple computer owners.

Robert Freeman, a senior research analyst for Input, a computer market research firm in Mountain View, Calif., says the first-time user has difficulties running a computer and could use the help of a computer store.

When he got an Apple III, Mr. Freeman read the operating manual. ''It wasn't quite incomprehensible,'' he said, ''but given the value of my time, it wasn't worth it. I called the computer store and said I needed two hours of training. For $100 they walked me through it.''

''It's false economy to save $1,000'' and give up the service, guarantees, and support from a specialized computer or office supplies store, agrees Steve Epner, president of the User Group Inc., a St. Louis-based computer consulting firm.

Consumers shopping for personal computers can go to a number of places to get the equipment they need. At the computer specialty retailers - which include independent dealers and manufacturer product centers - they will pay more but will also get more help and guarantees. Many computer stores now offer classes for beginners. And some department stores, such as Macy's in New York and Famous Barr in the Midwest, have joined the ranks of computer retailers, too, hiring informed salespeople and offering product service and help.

As service drops, so does price. Lower-priced computers can be found at discount merchandisers such as K mart or Venture, at hi-fi stores, in computer catalogs, and sometimes in newspaper classifieds, where ads for used computers can be found. A few independent computer dealers are offering trade-ins, but stores that sell only used personal computers haven't evolved yet.

Robert Donohue-Evans, editor of Computer Retail News in Manhasset, N.Y., says that in the past nine months ''there's been a split'' in the way computers are marketed. Computers costing less than $300 are being sold through the mass merchandisers, including grocery and stereo stores in some areas. These stores may offer product demonstrations and will take back returned products, but that's about the extent of their service, Mr. Donohue-Evans says.

''Some of these products are easier to use,'' however, and don't require much training, he adds. ''People will have some sort of struggle in getting them to run. . . . But for the money, I don't think it's a raw deal at all.''

''Very few computer stores sell these (the lower-priced) products anymore,'' Mr. Donohue-Evans explains. ''The Apples, the IBMs, the Osbornes - that's what the specialty computer stores are sticking to. They want to hit professionals who aren't going to bargain down on price and who want to pay for training and support.''

But computer marketing has become competitive, and the higher-priced computer stores are doing their best to attract customers who keep hearing about great discounts in other places. These stores have periodic sales; include software or extra equipment, such as printers, in the purchase price; and emphasize service.

Mail order and discount stores aren't taboo for everyone, consultants and users say. ''If you know exactly what you want and have some experience,'' shopping at these places can be a good idea, says Mr. Weiglin, the Apple Orchard editor. Most of the items people buy from mail order or discount houses are software and peripherals (computer extras such as disk drives, printers, and phone modems), he adds.