The iPhone 2G.
Yes, you can buy international iPhone's version (a iPhone with out Internet) in eBay or amazon, some iPhone that sell outside U.S, is international iPhone' version. You can use it with any network that you like.
An iPhone 5 is the latest version of the iPhone. The iPhone 5 is the lightest and slimmest of all the iPhone models.
Just download the iPhone version. There is no native iPad version, but you can get the iPhone version and it should run just fine.
The latest version of the Apple iPhone is the iPhone 4s. It is visually identical to other iPhone models but it is most advanced in terms of hardware and software.
No. Your iphone should be 3G version or later.
The white iPhone 3G 16GB
The iPad's version of Garageband will not work on an iPhone.
Go to: Settings --> General --> About --> Version (x.x)
This is the current version of iPhone sftware but the newest version which is called OS 4.0 is out Summer 2010, most likely June 2010.
Sadly, no. The latest version of the 3rd iPhone (iPhone 3GS) is iOS 6.1.5.
I don't believe the iPhone 3G can update past 4.2.1, but any newer iPhone can update the same way you normally update an iPhone through your iTunes authorized computer.
It depends on the version