1. See my User Tip for some help: Some Solutions for Resetting Forgotten Security Questions: Apple Support Communities.
2. Here are two different but direct methods:
a. Send Apple an email request at: Apple - Support - iTunes Store - Contact Us.
b. Call Apple Support in your country: Customer Service: Contacting Apple for support
3. For other queries about Apple ID see Frequently asked questions about Apple ID.
Click here and search the article for '2 out of 3' without the quotes; if you've forgotten the answers, this generally involves either a message being sent to your rescue email address or contacting the iTunes Store staff directly.