COMPUTERS BENEFIT INSURANCE AGENTS

Tom Reardon, an independent insurance agent in Oyster Bay, L.I., communicates these days with the Travelers Corporation, one of the insurance companies he represents, by computer. ''With the computer,'' he said, ''we can issue auto policies the day after the person comes in, we can send messages to the company and we can give instantaneous quoting.''

Mr. Reardon's agency, Reardon-Raplee-Lindner & Mehlman, has spent about $45,000 for computer equipment, but he thinks that it has been money well spent. ''If we didn't have it, it would have probably necessitated hiring someone else,'' he said. ''We have saved thousands of hours worth of work and thousands of dollars. And it's impressive for your customers.''

Thousands of independent insurance agents such as Mr. Reardon are beginning to link up by computer with the property and casualty insurers whose policies they sell.

Although some major insurance companies have long had computerization at their headquarters, and some large national insurance brokerage firms have long used stand-alone computers for internal functions, the independents have been slow to purchase the equipment necessary to communicate electronically with insurers. Costs of Equipment High

The costs of such two-way communications equipment are high, and there have been difficulties in establishing links through a single computer system at the offices of the 60,000 or so independent agents and brokers, known in the industry as ''producers,'' who may sell various automobile, homeowner and other policies of 10 or more different insurers.

Indeed, many insurance executives say it probably will be the end of the decade before computers are widely used in the field. ''The technology is there,'' said Richard J. Kasyjanski, director of research of the Independent Insurance Agents of America, a national agents association, ''but right now the insurance industry is not very sophisticated with automation.''