It depends on your information and what all they need from you. If you call the IRS they can pull up your return and give you the information. They recommended faxing when I called. Said if you fax it, your return will be delayed 6-10 weeks, if you mail it expect a delay of 8-16 weeks. It took me 5 days just to get the fax to go thru because the line was constantly busy.
