I need a little help to find my uncles wife and children

@ Kjell Odding

I found a Family Grouping in San Francisco that shows:

Arne J. Nilssen who would be 83 if living
Ruth R. Nilssen who would be 83 now. (Wife?)
Sonja or Sonia Nilssen who is 45 now. (Daughter?)
and someone else who is related named
Ritva Nilssen who would be 79 if living

Sorry I have no further information but it might be a helpful start for you.

YES - splendent. Ruth - I heard that name before. It must be his wife. Where do you fond this? Thankyou

I checked a site: www.intelius.com
The information is not always up to date but it does often help in locating people who were or are living in the USA and place or places where they live or lived.
I have found that the information can be up to 5 years outdated but it does give one some reference point.

Very good. I tried google and some other searchengines but this site look better. Thank you for help.

Here are another two "people finders that I use"

lookupanyone.com -

https://www.lookupanyone.com/search-summary-out.php?ReportType=1&am...

pipl.com -

http://www.pipl.com/search/?FirstName=Arne&LastName=Nilssen&amp...

Pipl.com - there I find more. Thank you.

I've added a wife and two children to my uncle

@Kjell, there's also the SSDI (Social Security Death Index), for those who are US citizens, and relatively recent - some births go back to the 1890s, deaths might go back to the 60s. Not everyone is listed of course, but it does help if one isn't sure if someone has died. Go to www.rootsweb.com, scroll down to Social Security Death Index/SSDI, and it will take you to the page. Sometimes it's better to use just the surname for the search if the name isn't too common. Advanced search allows for state of SS# issue, last place of residence, etc.
There's also 411.com - telephone directory that I've found very useful. And zabasearch.com as a cross reference for peoplefinders.com and intelius.

Kjell Odding

I found a Sonja Niissen (about 45 years old) in Lower Lake, California related to the only Arne Johan Nilssen in California.. She also has been known as Sonja Givens and is related to Kenneth A. Nilssen (born November 11, 1961).
I found a phone number and address for him which I will email to you.

Ritva R. Nilssen is also known as Ruth Nilssen, and I have her listed as being about 79 years old. I found a phone number and address for her as well. She is also known as Ruth.

Name: Keith Alan Givens
Spouse: Sonja Carol Nilssen
Marriage: 20 Oct 1990 - Douglas
Residence: California
Residence: California

They ARE elusive. Is that ALL you know about them?

www.lookupanyone.com tells me that there are three (most likely same person) Sonja C. Nilssen in California, Santa Rosa specifically. But she's aged 45, so probably too young to be your Uncle's wife?

If I search Google for "Santa Rosa, Sonja Nilssen", I find
an interesting artist - http://www.artslant.com/global/artists/show/21561-sonja-nilsson

and a "Ring Steward", whatever THAT is at the Mt. Diablo Dog Training Club - http://www.mddtc.org/tales/2005-nov.tales.pdf

HA! Bingo.

Check out first person on THIS link: So she IS a mere 45.
http://radaris.com/p/Sonja/Nilssen/NY/

Not MUCH to go on. But that certainly narrows down their location. That site even "offers" a free trial of some sort.