Called but hung up when they got the answering machine. Tried to call back but only got busy signal

called. no caller id and didn't leave a message

Local Services more telemarketers

Called on a Sunday.  Claimed to be from IRS.  Wanted to verify my business address.  Sounded like foriegn telemarketer.

http://www.irs.gov/uac/Tax-Scams-Consumer-Alerts
http://800notes.com/forum/ta-8c2f64bf2b91fa5/irs-warns-of-telephone-scam

Report the Calls to the real IRS here:
•report the incident to the Treasury Inspector General for Tax Administration at 800-366-4484.
•You can also file a complaint with the Federal Trade Commission at FTC.gov. Add "IRS Telephone Scam" to the comments in your complaint.

******
Do consider maybe getting a call blocking device or phone.. You can google them and many are around $60.00 or so.