Consulate took like 28 days(after receiving my file from NVC) to send me packet 3
It's very hard to contact the embassy for interview, I have been calling the phone number they gave on packet 3 in vain.
hope they will finally pick up.
My fiancee still have to make an appointement and go to interview.
Packet 3 is basicaly the list of forms you need for interview.
you gathered all the required document, call the embassy to set up appointment, and do medical exam(as recomended by consulate) 2 weeks prior to interview date.