The downside of privacy

One of the negative aspects of privacy is that it's now impossibly hard to get information about people. I've been searching for the woman listed on my father's death certificate as his wife for nearly 10 years now. I cannot find her. Now, it's been almost 20 years since he died, so I assume her name has changed, but I cannot even find a record of her marriage to my father, which tells me it likely happened after 1985, since everything before that is indexed and available online, but nothing else. Her name is almost as common as my dad's, and I can find no record of her under her maiden name, either. The last known address is a Salvation Army facility in Los Angeles--19 years ago.

Feh.