There are two airports in the immediate San Francisco area. Oakland International and San Francisco International airports.
They are easy to get in and out of - BART runs to both of them for inexpensive, quick travel. Please check the corresponding website for serving airlines and ground transportation information.
For airfare information you can check out a really nice fare search engine at qixo.com and cheapfares.com.
There is so much to do and see in the San Francisco area. One of the best websites for haps in the city is sfstation.com and second runner is sanfrancisco.citysearch.com. Theatre, concerts, nightlife, art exhibits, and other wonderful bay area attractions are listed in great length at these sites. There is wonderful hiking along the west marin headlands and ocean beach that streches for miles along the Pacific Ocean on the edge of san Francisco.
Ukiah has many accommodations. It's good to arrange hotels in advance since there is an expected Soccer Tournament that same weekend and hotels are booking fast.