ADP handles a great deal of the payroll in the US. Depending on the level of service chosen and the size of your employer, W-2s will be available at different times throughout the month of January. However, in general, they are very quick to process them and most have their W-2s available online considerable before the paper copies arrive in the mail.
In general, your employer can update you on the progress but normally can do little to expedite it.
