catera,
I work at Logan, it's a cinch. I don't know whether you're doing FedEx or airline but they are all together. Follow signs for Harborside Dr.. They are all along that road, past the Hyatt hotel, and most are on your left hand side,whichever airline it is just look for door that says "customer service" or entrance, and just make sure you have a picture I.D.
Ray