If you think finding the perfect engagement ring or wedding dress is hard, just try finding the perfect rabbi.

Sonja Rothkop finally found the perfect fit -- on the seventh try.

For Rothkop and other local Jews who don't belong to congregations, finding the right rabbi to do the nuptial honors isn't always easy. In fact, some say choosing a rabbi is one of the most complicated, time-consuming and potentially frustrating pre-wedding tasks.

Rothkop, a 46-year-old freelance writer, and David Hyams, a 49-year-old operations manager at the San Francisco Chronicle, searched extensively before finally finding Rabbi Michael Robinson, who will perform their wedding ceremony next month.

On the road to Robinson were rabbis on sabbatical, rabbis who never called back, rabbis who were busy that day, rabbis who felt uncomfortable that Rothkop never got a Jewish divorce when her first marriage ended more than 20 years ago.

The couple met rabbis who were witty, who were warm, who were terrific.

They weren't available.

For one thing, the couple wanted to get married somewhat far afield, in Bodega Bay. It's a shlep for many rabbis, especially because the wedding day, Feb. 9 -- the anniversary of the day the couple met -- is a Friday. Most congregational rabbis wouldn't be able to make it back from the wedding in time to lead Shabbat services.

Finally, Rothkop let her fingers do the walking through the Sonoma County Yellow Pages and found her rabbi, who is the spiritual leader of Congregation Shomrei Torah in Santa Rosa.

"He's a hiker, an outdoorsman, a social activist. We didn't know what we wanted in a ceremony, but the words that came out of his mouth were my fantasy. He's very good with second marriages," says Rothkop, spilling over with enthusiasm about the rabbi she finally found.

"On the phone, he said, `Come up so you can see if I'm the right guy for you.' I just loved that."

Finding the right rabbi is even more of a challenge for interfaith couples, whom just a handful of local rabbis will agree to marry. Jewish Community Information & Referral and the Interfaith Connection both say they field numerous calls from such couples shopping for rabbis.

Jeff and Michelle Leopold were married last July, after interviewing almost a dozen potential rabbis. Michelle is what she calls "agnostic Protestant" and her new husband is Jewish.

"We already decided when we got engaged that we'd be married by a rabbi, under a chuppah, with most elements of a Jewish wedding. We already decided to raise our children Jewish and have a Jewish household," she says.

Leopold, director of marketing at the St. Francis Hotel in San Francisco, says she "thought finding a rabbi would be a piece of cake."

More like a cake thrown in her face, says Leopold, who "ended up in tears" after her first few attempts to approach rabbis.

"It was so upsetting. I was willing to give so much, and I wasn't asking much in return," says the bride, who wanted the ceremony to include legal vows such as "Do you take this man to be your lawfully wedded husband?" She also wanted her father to be asked if he was willing to give away his daughter, as is customary in many Christian services.

"We had talked about that since I was a little girl. But everyone said `no,'" Leopold recalls.

After hours of interviews, she finally found Rabbi Charles Familant of Menlo Park, who was willing to create the kind of Jewish ceremony the couple wanted.

"It was absolutely wonderful in the end," she remembers. "A happy ending."

For those couples who don't belong to synagogues or are new to the Bay Area but who seek a rabbi to perform their wedding, Rabbi H. David Teitelbaum of the Board of Rabbis in San Francisco has some clear-cut advice: "If the first thing the rabbi says is `Mazel tov,' you know you've got a good person."

In addition to counseling a couple on the ceremony itself, he says a rabbi should spend at least several additional hours with a couple, discussing how they metand what they love about each other.

A rabbi should also counsel the couple about their relationship and their expectations of married life, Teitelbaum adds. If a rabbi doesn't get the couple talking realistically about their hopes for the future, he or she may not be the best rabbi for such an important occasion.

While a good ear and sturdy car are often useful attributes, Teitelbaum always tells couples to look for "a good rapport with the rabbi. There should be a very frank and warm relationship. That's very important."