Volunteers and interns get one foot in the job door

''Looking for work.'' That's how many Americans describe their activities these days. Some have found a new way of approaching the problem - through volunteering and interning.

These people are not working gratis simply to satisfy a desire for useful activity. Their volunteer jobs and internships are purposeful steps that could ultimately place them in paying jobs much faster than want ads or agencies could.

''I was a teacher for 10 years,'' says Nancy Watkins, now director of the Volunteer Bureau in San Diego (a paying job). ''When I moved to a different area where I didn't have teaching credentials, I had to reevaluate my career. That's when I started volunteering for women's organizations.'' Through the experience gained and the network of contacts made through volunteering, Ms. Watkins was able to secure her present job, as well as paid employment with a public television station and a senator's political campaign.

Besides cultivating useful personal and organizational contacts, any job experience, paid or unpaid, that can be added to a resume is also important in getting a job.

There are cases where people obtain paying jobs directly from volunteer work. A YWCA in Irving, Texas, was so impressed by a 17-year-old volunteer that it offered her a job only one week after she started. But these cases are rare, says Robert Adams, Manager of Volunteer Services for Chicago's Volunteer Action Center, a division of the United Way. ''Too many people are offering to volunteer in hopes of finding a job. Some get pretty angry when, after a few weeks of volunteering, the agency doesn't offer to pay them.''

Internships can also offer the job seeker a better chance.

Volunteering and interning are similar in that both are nonpaying jobs. The difference between the two is more difficult to define. Dr. Debora Sherman, Executive Director of the nonprofit Career and Volunteer Advisory Service (CVAS) in Boston, says, ''internships are much more finite and structured than volunteer jobs.'' Furthermore, an intern is clearly looking to obtain skills or make contacts that will eventually lead to paid employment - either within the organization at which they're an intern or somewhere else. Volunteerism more often involves work for organizations or social causes someone feels strongly about, such as a political campaign.

Internships are commonly suggested as part of a college or graduate curriculum. Students, however, are not the only people for which interning has been valuable. People who want a career change, as well as women who have been homemakers for many years, are finding that internships help meet their employment needs.

Vera Gropper was a homemaker for eighteen years. Two years ago she decided to go back to work. She searched want ads and bought books on how to find a job. Having no success, she tried Project Re-entry - a program developed by CVAS to provide career counseling and internship placement for women like Mrs. Gropper.

''Before I joined Project Re-entry, I didn't know what I was looking for in a job,'' said Mrs. Gropper. ''But after the first month of classes where I was talking with women who were in the same position as myself, I realized the problem for most of us was that we were afraid . . . that we couldn't match up to the people who were involved in the job market while we were at home. Project Re-entry helped us to overcome this.''

Project Re-entry is one of a dozen or so similar programs cropping up around the US. Since 1976 the program claims to have placed 300 women in internships; 85 percent of those women who wanted a paying job are employed, and 42 percent are working at the organization in which they interned. Salaries range from $8, 000 to $35,000 a year.

The fee for the program is $950 (financial aid is available for those who qualify). This includes one month of workshops, meeting three times a week for two hours, and placement in a five-month internship.

Dr. Sherman and Sandra Kahn, director of Project Re-entry, have recently completed a book entitled, ''On Your Way: A Workbook for Volunteers and Interns, '' which tells readers how to select and obtain volunteer work and internships.