If you did not provide your bank account information on your tax return, you will get by paper check.
In the first lot only those whose return was processed by April 15, 2008 are getting the rebate.
Go to
Internal Revenue Service. Click Where is my Refund? Then click Status of my Stimulus Rebate. or #01-866-234-2942
For information on stimulus tax rebate read:
Your U.S. Tax Return: Are You Eligible for 2008 Stimulus Tax Rebate Payment?