Watch the Miles to Go online guitar lesson by Brad Carlton from Chord Studies: Rock and Pop Progressions Vol. 1
Some "Popular" chord changes are called that for a simple reason - you see them time and time again! This is one that will be sure to keep coming at you, so make sure you can switch these fluidly. Use your 3rd finger as a "pivot" to go between all three chords - it never leaves the 2nd string 3rd fret!