Does gravitational acceleration differ where you are on the earth?

Answer 1

Yes, elevation above the gravitational center of the earth matters. The farther away, the less gravity. Thus, you weigh less in Denver than in Miami.

Answer 2

In addition to what alikasam said, gravity differs depending on the density of the rock (or sediments, or whatever else is there) beneath you. It is a common technique in geophysics to employ a gravitometer to check for differences in gravity and then calculating what could be underground causing the anomaly.

Answer 3

slightly, depending on altitude, but not much.