Actually shrinking pores isn't really doable, pore size is somewhat determined by your genetics, but there are things that you can do to make them less obvious. Cleansing with a Clarisonic did wonders for making my pores less obvious by cleaning out all the gunk that was visible! Plus I got less breakouts and blackheads, which I am thrilled about! Clarisonic now makes the Mia which is a smaller version of the big brush, costs less and does an excellent job on faces.
Perricone MD Intensive Pore Minimizer is a good treatment which minimizes the look of pores, cleans them out and improves skin tone and texture.