Hmm.....Maybe check to make sure your sway bar endlinks are tight, and also check your shocks. Sometimes loose shocks can cause noise. They shouldn't have taken them off to do the drop, but it may have loosened up. You said it sounds like the front, but you might want to check the rear shock extenders too, just incase.
Besides that, you could check for play in the front wheels. It's newer, so it shouldn't have any, but maybe the wheels are stressing it out. Jack one wheel up at a time, normally I jack from the lower control arm. Then grab the wheel at 12 and 6 and see if there is any play. If there is, try to look to see if you can see where it's coming from. It's either the balljoints, or the wheel hub/bearings. Then grab from 9 and 3 and check for play. If there is play there, it could be the hub again, or it could be the tie rods, pitman, or idler arm. Some play is normal, but anything over 1/2"-3/4" of wheel movement would be a problem.