the issue here is when there is 'none' option when creating a new apple id not existing.
i had the same dillema when i was making my 1st apple id. after reading through different guides and forums all is offering the same answer on how to get this done, create new apple id! w/c i don't agree and refuse to agree.
One thing is common on this kind of issue (missing 'none' option under billing) that is you opened itunes > registered your account (i guess from a pc like i did!)
For 1st time Apple ID registration (meaning you never ever and ever have tried registering/using your preferred apple id/e-mail address)
1. Open iTunes
2. Go to iTunes Store
3. Search and install any 'Free' App (Facebook, Find My iPhone, etc)
4. Follow the step by step instructions
5. And under billing you should have 'none' option
Now let's say you were as excited as me to register your 1st Apple ID and you skipped the steps above and is now having issues w/ missing 'none' option there are two (2) approach you can do.
1. Create a new Apple ID and follow steps above -yes! that easy. Although you haven't finished the part for the billing due to the missing 'none', the Apple ID you entered is already registered and cannot be used anymore unless you finish the billing.
2.If you wish to keep your Apple ID without making a new one then Do Steps Below! -maybe it's not just me but the 1st Apple ID i used is what i really want so creating a new one is a no no! So if you would like to stick with your used Apple ID and encounters the issue above. So thinking out of the box i came up with the steps below which should help you like it did to me!
But you need to have:
1. Another Apple ID (say a temporary Apple ID since you don't like it and hopefully you finished the steps above)
2. Another e-mail address
When you have these then let's go!
2.1 Login to your Apple ID(Phone/PC) the one with the missing 'none' at https://appleid.apple.com
2.2.Click 'Manage Account'
2.3 Under 'Apple ID and Primary Email Address' click edit
2.4 Remove your Apple ID (seven/seven@mail.com which ever it is)
2.5 Put your other e-mail account
2.6 Hit 'Save Changes'
2.7 Login to the Apple ID you successfully created (but not the one you preferred!)
2.8.Click 'Manage Account'
2.9 Under 'Apple ID and Primary Email Address' click edit
2.10 Remove your Apple ID (seven/seven@mail.com which ever it is)
2.11 Enter your desired/original/preferred Apple ID
2.12 Hit 'Save Changes'
2.13 Open iTunes
2.14 Problem solved!
This is a long and tedious task but if you really wanted to keep your Apple ID then it's going to be worth it!
Sorry for the long post. Hope it helps!