I've gotten these and mastitis several times. Here's what worked every time for me. 1) Put a heating pad on the spot, or put a damp washcloth in the microwave, heat it up, and put it on the spot. For me, the hotter the better. 2) Then, massage the area in a "down and out motion" -- think of moving the milk toward the nipple. 3) Nurse your baby. Wherever the clog is, put the baby's chin toward that spot. Yes, this may mean some crazy positions. I once had my son laying up over my shoulder while I was flat on my back to try to get rid of a clog that was at the top outer side of my breast. This tip came directly from a pro lactation consultant. 4) Up your fluid intake.
I tend to do the massage along with the nursing at the same time. I hope it works for you. They can get really painful.
K.