Ahhh, you haven't stated what the facts are for fraud although, since it's been five years, you really ought to speak with a lawyer as to how to proceed. There are several skilled lawyers on Avvo.
More info is needed to properly answer your question. What is the "fraud" that you claim occured? Please note that the fraud must have been about something vital to the relationship that directly affected why the party who was deceived (you) agreed to the marriage. Some examples are marrying only to get a green card or hiding the inability to have children.
As for the statute of limitations, an annulment on grounds of fraud must be filed within 4 years of discovering the fraud.
You can learn more about CA annulments here: http://www.courts.ca.gov/1037.htm
Sign up to receive a 10-part series of useful information and legal advice about the divorce process.