Try this link, and click on "Scottish fiddling in Sacramento" (though I don't live in the area so I don't know anything about it).  But it should help you plug in.  No doubt the trad fiddlers will tend to know each other.

http://www.scotsfiddle.com

Also, these people should be able to help you - they seem to be quite active in the scene there:

http://www.rscds-sacramento.org/branchinfo.htm