Once your next payment would reach or exceed $600 or the year you have to send DP a W-9 form before they can issue that payment. You can find the form online and fax it to them (they do need a real signature). I scanned it and sent it as an attachment.
@belarus, make sure you send the email to both email@example.com AND firstname.lastname@example.org. I just addressed it to one and CC it to the other. You might have already seen that, though :) Good luck to your Giants!