Here's a list of celebrity (and semi-celeb) customers of 100% Rocking Chair in Los Angeles (1992-1997) and of Rocking Chairs 100% in Corte Madera (1998-2003) and in San Rafael (2003-?) the last two locations distinguished by * & ** respectively. I know there were others but if I can't remember them maybe it means they aren't really celebrities.
In alphabetical order:
Leslie Abramson
Roger Avary
Paula Barbieri
Fax Bahr
Kim Basinger
Annette Benning
*James L. Brooks
Nancy Cartwright
Clint Eastwood
Frances Fisher
Sam Fuller
Tom Gammill
Jonathan Gold
Johnny Grant
*Leslie Harlib
*Quincy Jones
**Kerry Kittles
Ricki Lake
Michael Learned
*George Lucas (for the Lucasfilm/Skywalker Ranch day care center)
Peter Lurye
William H. Macy
Madonna
Doug McHenry
Jason Miller
Max Pross
Eric Roberts
Rene Russo
Vincent Schiavelli
*Michael Schwab
*Jeremy Sewall
Brad Silberling
Richard Simmons
Ross Thomas
Suzanne Vega
James Worthy
Dwight Yoakum