Tickets for the luncheon, held at the home of Silicon Valley entrepreneur and philanthropist Thomas Siebel and his wife Stacey, range from $1,000 for lunch alone to $2,500 for lunch and a John McCain 2008 lapel pin.
The posting on the Web site is an invitation to attend from the McCain-Palin Victory California Leadership Team.
Host Committee members - those who donate or commit to raise at least $10,000 - will be given tickets for a reception at noon with photo opportunities in addition to lunch tickets.
The regular luncheon is scheduled to begin at 12:30 p.m., with Palin offering remarks at the event, according to the California Republican Party Web site.
RSVPs and donations for the event must be made by Sept. 22 and will not be accepted at the door. Attendees are asked to arrive early due to security measures and are asked to wear business attire.
Despite the posting on the prominent site, a spokesman for the McCain-Palin campaign declined to confirm the event is happening, saying it is too early to release travel plans.
Additional ticket information for those interested in attending the luncheon is available from Caitlin Ashlock at (310) 309-2101 or by e-mail at firstname.lastname@example.org.