This is just one of those things you've got to know: To look up information about a parcel, you'll probably need to go look at the tax assessor's records.
Nearly all counties in the US have a tax assessor's office with online records. Unfortunately, they're all different, with little consistency between them. Luckily, the method I outline below is doable in many other places with a little revision.
Here's what I did.
1. Look up the tax assessor's web site. That's a simple search:
[ tax assessor Santa Clara county parcel maps ]
...which gets you to the county's web site with the maps.
2. Navigate through the website to the parcel database.
... in this case, look at the left-hand side of the page (where the navigation
controls usually appear).
... there, you'll find a link labeled "Look up property records"
... keep on following links until you get to the page that's labeled
"County of Santa Clara ARI"
... fill out the form on this page
3. Click on the link labeled "Assessor map"
... Note that there are two links to look at maps. One just give you a regular map,
... the other is the "Assessor's Map" (aka "a plat") which has all of the parcels for the
... county (or city) on it.
And... the one thing you've got to know is that Assessor's maps also have a great deal of extra information--such as acreage per parcel. In this case, you can just look at the map and read off the acreage.
I've had people in my classes complain that "all you're doing is teaching us tricks!"
I wish there was a deep, rich, meta-theoretically clean model I could give you -- but the truth is, a great deal of being a great researcher is knowing what's possible to find, and how to find it. In the general case of tax / city / county plat information, you've got to go mine it out of the county's deep web.
But at least now you know how!