Where to buy a factory unlocked iphone?

Where is a reputable place to buy a factory unlocked iphone (no ebay please).It doesn't have to be the newest model but want a new or maybe used factory unlocked iphone.

Why won't itunes download on my computer? ERGENT

When i try and download itunes it says that "Content was blocked because it was not signed by a valid security certificate.

For more information, see "Certificate Errors" in Internet Explorer Help.

What should I do i need itunes on my computer to get my new iphone 4s set up. Please give me answers quick!

I use up a lot of my iphone 4 data

2 days ago i got an alert saying i used up 51% & i just got another alert today saying i used 75%. The data is shared between my dad and my stepmother and they barely use it. I keep my Wi-Fi on when i'm at home but it still uses up the data, somebody suggested to turn off " cellular data ", what's that going to do?

How to turn off a number on my iphone?

Me and my brother were on a contract with Sprint and then we switched to AT&T. Along with the switch the company also switched our numbers. So in order for me to get all my old apps and stuff on my phone i had to back up my new iphone to the old one through icloud. Now whenever I send a message to my brother, I'm basically sending a message to myself.

Can a unlocked iPhone 5 use any sim card that has a data plan?

I'm planing to buy a unlocked iphone 5(which i have to pay the full price of $999), i'm currently using a galaxy note and have a data plan and was wondering if i could use the sim card that has my data plan on the unlocked iPhone?

Added (1). I mean i now have a 12gb cap on my internet for a very reasonable price and i would like to continue to have that 12gb of internet on my iphone 5 without getting a new plan

Can you change over numbers on an IPhone manually?

Many people that have an iphone will know that if you go to

settings>phone>it says number

can you swap over the number from one phone to another

for example

my mum has an iphone 3gs and just brought an iphone 4 can she use the settings method above to switch the numbers over without anything going wrong?

Should I sell my iPhone 4 or 5?

I have a ipad 2, I also have an iPhone 4 on contract, but isn't used that much now because of the ipad.
Next week I can upgrade my contract and get a free iPhone 5! Now I'm unsure whether to seek the 4 or 5, is their much point of keeping then if I have a ipad, especially if I can get £400-£500 for the iPhone 5!

Unlock iPhone 4S from network?

I've recently bought an iPhone 5 so I've decided to give my old 4S to a friend as her phone is somewhat knackered.

The 4S is currently locked to the Three (3) network, is there any way to unlock it without asking the network? The phone is jailbroken but I can't use cydia to unlock it as the sim is smaller in the 5. I know I can get a converter for the sim but I'm not sure if the sim would work in it anyway.