That iTunes one is very typical, Amazon, Kindle, PayPal and the online banks are frequently the subjects of these phishing attacks also. You'll probably find that no such charge has been made to your account, but never ever click on the link in this type of email. You can pretty much be guaranteed it will take you to a site that will compromise your computer.
Any time you get an email that sounds anything like this from a bank or service provider, go directly to the providers own website to investigate. Never click on the links provided or open attachments, especially .pdf or .zip files.