Janna, Yes, taxes do vary; however, in Alameda the taxes are USUALLY going to be based upon 1.25% of the purchase price. Some areas of California have Mella Roos assessments (for infrastructure buildouts of streets, utilities, schools, fire departments, etc); however, Alameda is a long developed area and I do not recall any major new developments.
Remember, in California, our property taxes are based upon the purchase price and it will not assist you at all to know what the current owners are paying. Because of Prop 13 (passed back in the 80's), long time homeowners can have very, very low taxes as opposed to a new purchase. 1.25% should get you pretty close to the actual figures.