Obituaries were/are provided by friends or family. If no one submitted one to a newspaper, then there usually wouldn't be one.

But, how to find relatives? Here are some options: (1) probate records (if there was a will)--check with the probate department of Alameda county; (2) mortuary records; if you search on "san leandro mortuary" in Google, you will be able to find some local funeral homes; and, (3) cemetery records.

As for the Social Security Administration, they have a webpage outlining how to request information and what information they will release:

http://www.ssa.gov/foia/foia_guide.htm

It's not clear whether they would give out the info on Laurel's last address (probably a retirement home), but it couldn't hurt to try.

Good luck.