www.vitalrec.com can tell you where to obtain the death certs...which could be important, as a child of theirs may be listed as the reporting party and the address for the reporting party should be on the death cert.vitalrec.com will lead you to the proper county where you should order the death cert....or you can order directly from them and pay a little more and maybe get it a little quicker....However, the choice is yours and there is no fee if you just go to the site to find out where to write and how much it costs for each county.
As for obits...There's a couple ways...I prefer and have had better luck looking up CA public libraries on the internet and finding the appropriate county or city (if it's really a larger town/city) and phoning them with the info I have.They seem much more willing to do your search (than local newspapers) and charge you a reasonable rate $5-10 to send you a copy of the obit.
However, if you go to www.yahoo.com and click on newspapers....it will lead you to the listings they have for newspapers in various areas.
PS.In your posting you listed Clara Peterson Stenson as being born in Pueblo, CO (Colorado)... However, her death and the death of her husband were listed in cities/towns that are in California (CA)...Just wanted to be sure you knew the difference.I have done some different country searches for my own family and find I am often confused by townships/regions/counties, etc.