I took a deep breath and my heart pounded when I opened the letter from our son's college.

The bill for next year, we were told with great apologies for "inflation," would be $7,500. And that doesn't include special fees, books, transportation or beer.

What it adds up to is that parents and students starting out along the college trail could be paying in excess of $30,000 for four years -- more if it's a private school, less if it's state or city.

Our son will be a senior -- his last year. When he started as a freshman, the bill was around $5,000. You can see what inflation is doing to families' college money.

This means that many of us have to hustle for loans, work-study programs, good colleges or universities at lower cost -- anything that will help staunch the money flow.

We got a guaranteed student loan from our bank last year and hope to get one this fall. You can get up to $2,500 for each academic year with a maximum of $7,500. Interest is only 7 percent and you get stretched-out, easy payments. Most important, they don't take into account how much money you make or how much you have in assets. Theoretically, you could be a millionaire. For most of us, more money is needed, and for families with two or more students in college at the same time, it can be a financial disaster.

The problem is, most families don't realize how many sources of funds are available to help finance a college education. There's money all over the place if you know where to find it and how to negotiate for it.

It's all explained in fascinating detail in a new paperback edition of a book called "Financing College Education" by Kenneth A. Kohl and Irene C. Kohl (Harper & Row, $4.95).

I was able to talk to Ken Kohl, who is the chief financial-aid officer for Georgetown University. Prior to his Georgetown job, Kohl was the director of the guaranteed student-loan program in the Department of Health Education and Welfare, and before that he was the financial aid officer for Princeton University.

He knows his stuff. He helped me map out a financial plan for my son's last year at college and readied me for the next son coming along in high school. Kohl and his wife, Irene, of course, had to work out their own financial plans for their own children. Kohl has helped thousands of parents and students over the years.

Kohl says you have to start your planning early. Begin to figure out the kind of college or university the student might attend. Get some rough cost estimates.

"Some parents," says Kohl, "find that a son or daughter doesn't want to go to college right away. In this case, you should work out a job program where the student can get some training in a field of interest, earn some money and be better prepared to go to college a year or two later."

Kohl's book shows how to negotiate for guaranteed student loans through local banks and savings institutions.

"There's even a government lender of last resort in most states," Kohl says, "if you can't get money locally."

Kohl advises that you get to know the financial-aid officer in the college or university the student might like to attend. The officer can help direct your search for funds. And so can the Kohls' book. It's a lifesaver for parents and students. You can get a copy at your local bookstore. The price is $5.70 (with postage and handling) from the publishers, Harper & Row, Attn: Ruth Brengel, 10 E. 53rd St., New York, N.Y. 10022.