With 1,200 funds to choose from, an adviser may be for you. You needn't be a Getty to get some outside aid on making your choices

OK, so you want to put some cash in a mutual fund. Or you're already in a fund that's doing pretty well, but to diversify, you'd like to find another. Great. You've got some 1,200 equity funds to choose from. Even if that list is pared down according to how much risk you can take, your age, and investment goals, there might be several dozen funds to wade through.

One way to clear through the ever-thickening thicket of mutual funds is an advisory service. As the number of funds has continued to increase, so has the number of these services, as has the range of clients they serve. Institutional investors have been using these services for several years; now individuals can sign up.

Some of the services stick with one company or ``family'' of funds; others manage all their customers' money together as a unit; and a few invest each client's money differently, though they may only use a few funds.

One fund finder, Cambridge Analytic, a division of the Cambridge Group in Newton, Mass., began operating earlier this year. It handles accounts as small as $7,000, though the minimum may go up to $15,000 next year, says Joesph Deitch, president of the Cambridge Group. The fee for the service is 2 percent of the account, scaling down to 0.6 percent for accounts greater than $5 million.

For this fee, the company will analyze the perfomance of more than 1,000 portfolio managers, looking for the best performance in relation to the risk, or beta, of the portfolio. Five portfolio managers will be selected for each client. The selection will be based on the client's age, goals, and overall financial circumstances.

The service now has about 100 customers and some $2 million invested, Mr. Deitch says. The size of the average account is about $22,000.

Two percent of $22,000 is $440, and that money could be saved by doing the research yourself, says John Markese, director of research at the American Association of Individual Investors.

``It doesn't take a lot of effort, if you start with no-load funds,'' Mr. Markese says. ``Then you decide what category of fund you want to be in. If it's income, you've narrowed it down to about 30 funds. Then find out about services. Do they have a money market fund where you can switch money if you want?''

After doing this, Markese contends, there aren't that many funds left on which to do extensive research on performance and risk. ``It's not that difficult.''

No, it's not difficult, Deitch agrees. ``You can do it yourself. Not only can you, but I will tell you step by step how we do it. I agree people could do it, but why?'' In addition to the $2 million handled by his service, Deitch points out, he invests some $19 million in general trust accounts. The same resources employed for those accounts are used here, he notes. When only about half of the fund managers are able to outperform the Standard & Poor's 500 at any given time, Deitch believes his service will find those who are beating the S&P.

Another selection service is available from Republic National Bank in New York, but the minimum investment is $150,000. The fee is 1 percent of assets, on top of any other fees or charges imposed by funds that Michael Hirsch, the bank's investment manager, selects. Fund selections are based on the individual investor's needs and goals.

``If John Q. Public is willing to take the time and money to do this, he can do it,'' Mr. Hirsch says. ``If he has the time to place 20 or 30 phone calls and do all the other reearch, he can handle it.''

Otherwise, Hirsch believes, an investor may find that his service, which he immodestly calls the ``wave of the future in mutual fund or multifund investing,'' simplifies things.

For investors who can't handle the $150,000, Republic also offers a service called FundTrust, with a $2,500 minimum. Unlike the larger-minimum service, this one is not tailored to an individual investor. Instead, FundTrust offers the same package of six no-load funds to everyone, charging a one-half percent management fee.

A different approach is offered by F.A. Spina & Co. of Melville, N.Y. ``We do not offer a menu of objectives,'' says company president Alan Levinson. ``We say this is our objective and we will pick funds to meet it.''

The objective, Mr. Levinson said, is ``long-term growth of capital without undue risk.'' To this end, the firm will spread assets among international funds, interest-sensitive stock funds, precious metals, and growth or value-oriented funds, he said.

The company looks for no-load funds and has a sliding annual fee of 2 percent on a minimum investment of $25,000. Over the past four years, the fund has had an average total return of about 18 percent a year, Levinson said.

He agrees that investors can do this research themselves, and some who have the time enjoy it, but ``very few people have the time, inclination, and expertise to do it. There are more than a thousand funds to choose from, and it's a constant effort of research and analysis to get the best return.''

Some mutual fund companies do the money-spreading on their own. Vanguard's Star Fund, for example, was started in 1985 and seeks capital growth and income by investing in other Vanguard common-stock and fixed-income funds. About 60 to 70 percent will be invested in Vanguard's Explorer I or II, or its Windsor I or II, and 20 to 40 percent will be placed in its GNMA fund or Money Market Trust.