Audi shops in Silicon Valley

One of my Audis, a 2000 A4 will soon be out of warranty (I purchased a 6y/100k extended warranty when I bought the vehicle).

I would greatly appreciate recommendations for topnotch Audi shops in Silicon Valley, in the area starting from Redwood City all the way south to Saratoga and Los Gatos.

I prefer independent specialist shops to Audi dealers ;-)

Thx,

dk