handsongourmet/FlickrFrog Hollow founder Al CourchesneFrog Hollow Farm has more than preserves, peaches, pears, and cherries to offer. In the past few years, the Brentwood farm has been pressing extra-virgin oil from its own olives. Taste the results at Sunday's harvest party at the East Bay farm, 11 a.m. to 3 p.m. at 11435 Brentwood Boulevard (at TK), Brentwood. Tickets are $30-$65, and include lunch (with wine from Brentwood's Bloomfield Vineyards), as well as the chance to win an orcha