1) about 2-4 weeks after you file it
2) No. They will give you a fingerprint appointment in the closest or 2nd closest USCIS office to where you live, on a date of their choosing. But once you have the appointment notice you can usually do a walk-in prior to the appointment date. And you may be able do a walk-in at a different location than the one they specify. But walk-ins are never guaranteed, and you can't call ahead of time to know if they will accept you*. They make the decision whether to accept walk-ins on a day-to-day, minute-to-minute basis when you show up, according to how busy or empty they are.
*(well, you can call, but they'll usually tell you NO on the phone because they don't know if they'll be busy when you show up)
Last edited by Jackolantern; 14th April 2010 at 09:42 AM.
EB3 ROW I-485 Approved: July 2007
USC: July 2013
I am a layman, not a lawyer. What I write here is not official or professional legal advice. In addition, my answers on this forum are specific to the scenarios discussed in each thread and should not be generalized to other situations.