I am looking for court cases involving Kathy Graham of Grass Valley,
also known as Kathy Paine or Kathy Paine Graham.

Grass Valley California?

Yes. Grass Valley, California.

According to the web site of the County of Nevada (Calif) Superior
Court, in which Grass Valley is located, there is a site for the
following case:

Case Calendar   

Appearance Details for:  GRAHAM, KATHY A. 
Case Number:  L66445 

  Case Type          Date         Time   City 
  Limited Civil     11/15/2002   10:00AM   Nevada City 

You (or a Google Answerer) can search the site yourself at:

http://www.court.co.nevada.ca.us/cgi/dba/casecal/db.cgi

and can contact the court for more details at:

Nevada County Civil/Family Law Courts (530) 265-1293

Whoops...that should have said a "cite" for the following case...

Thank you for the information about the upcoming case. Is there any
way to find out the particulars of the case, i.e., who is suing whom,
why, etc.? I went to the website but all it indicates is the
appearance date and time.

Also, what about previous court cases in Nevada County for this
individual, say, going back ten years?

You can learn the identity of the other party by going to the Superior
Court website and searching only for the case number - L66445 (do not
enter a name).
http://www.court.co.nevada.ca.us/cgi/dba/casecal/db.cgi

It will probably be possible for a researcher to find for you the
names of the parties for any additional cases involving Ms. Graham
filed in the County of Nevada (CA), but it is unlikely that they will
be able to tell you the subject matter of the suit. That information
is probably not available online, and it is probably only available by
ordering the physical records from the courthouse or visiting the
courthouse to inspect the actual files (which may be in storage).