Can I use a regular IEC cable with the iMac? I live in Europe and the power is 240v

If it is an iMac Intel, it supports any voltage. Only certain older G5s don't support it. To tell the difference, read my tip:

https://discussions.apple.com/docs/DOC-2455

The computer's PSU will auto-switch between 110 and 220 volt AC systems. You can use any power cable that has a 3-prong female end compatible with the male connector on the rear of the iMac.

Kappy, http://support.apple.com/kb/SP35 the earliest iMac Intel even says it goes all the way up to 240v.

The nomenclature has for decades been 110 and 220 volt. However, this covers 120 and 240 volt as well or 115 and 230 volt. Sorry if I confused you. 🙂

http://wiki.answers.com/Q/Are_220V_and_240V_the_same

Yes, just go to your local Apple Store or AASP and buy the correct power cord that matches the outlets in your specific country.

see > Apple - Find Locations

Any electrical store can supply you with an IEC cable a lot cheaper than Apple.

You can even get them in white.