it's looking like I might find myself in Lodi, CA this summer. Where does one go to shoot smallbore silhouette within a hour or so of Lodi?

topclass

http://www.nxtbook.com/nxtbooks/nra/ssusa_201204/
You can look up most of the sanctioned matches here.
Lodi, CA is in Northern CA and I am in Southern CA so that is the best I can do for you topclass

Sunnyvale Rod and Gun Club (http://www.sunnyvalegunclub.com) is about 100 miles from Lodi and has silhouette matches the 2nd Saturday of every month. Bit of a haul - hope you can find something closer.

Diablo Rod & Gun in Concord is about 50 miles from Lodi. http://diablorodandgun.com/ They shoot everything from air rifle to HP out to 200 at the Multipurpose range.

Sacramento Valley Shooting Center does BPCR and military silhouette. http://www.sacvalley.org/clubs.html

A little further from Diablo is the Chabot Gun Club http://www.chabotgunclub.com/. 200 meter modified HP and handgun

If your up for a road trip The Monterey Swiss Riffle Club http://www.theswissrifleclub.com/ does SB & HP the first Saturday of each month.

Jay