From IRS.gov …
Suspicious e-mail/Phishing:
Phishing (as in “fishing for information” and “hooking” victims) is a scam where Internet fraudsters send e-mail messages to trick unsuspecting victims into revealing personal and financial information that can be used to steal the victims’ identity. Current scams include phony emails which claim to come from the IRS and which lure the victims into the scam by telling them that they are due a tax refund.
You Can Help Shut Down Phishing Schemes
The good news is that you can help shut down these schemes and prevent others from being victimized. If you receive a suspicious email that claims to come from the IRS, you can relay that email to the IRS: phishing@irs.gov.
Follow instructions in the link below for sending the bogus email to ensure that it retains critical elements found in the original email. The IRS can use the information, URLs and links in the suspicious emails you send to trace the hosting Web site and alert authorities to help shut down the fraudulent sites.
Unfortunately, due to the expected volume, the IRS will not be able to acknowledge receipt or respond to you.