If the frame failed at the joint between the chain stay and drop-out then it's possible to have it soldered with a torch. It must be repaired by this low teperature process or the metal will soften and fail again. If you value the bike than take it to someone who is familiar with frame repair and fabrication. If the tubing or drop-out actually broke than you will certainly want to take the frame to a builder. Ask a good New York shop, club or check the net for leads.