how come I have not received my IRS refund check yet?

Should I have received it by now? But I haven'. Who should I contact if I should have received it.

There are 2 more batches of refunds to mail out. They mailed out the 2nd batch today.
Stimulus Refund Status https://sa1.www4.irs.gov/irfof/IRServlet?app=IRACTC&selectLanguage=en It will let you know if there is a delay with your stimulus payment. (for stimulus payment above) Regular Refund Status https://sa1.www4.irs.gov/irfof/lang/en/irfofgetstatus.jsp This one you can check for your regular refund from the irs I hope this helps
Have you done a amendment on your 2007 taxes, or do you owe back taxes? You can check your refund on the website Irs.gov
First have you check the IRS website "wheres my stimulus" and used the stimulus calculator to make sure you do qualify? Using the calculator will give you the amount you qualify for or don't qualify and the date to expect your rebate. Call 1-866-234-2942 for more information.