1) The eGo-T is like a lower powered kGo with a special tank and one piece atomizer, or heating, unit.
The special tank and atomizer are the parts that most people have trouble with and end up taking off and just using some other cartomizer or clearomizer instead. The kGo is a higher powered battery with more capacity. It doesn't include the special atomizer or tank, so you won't have to throw it away later. If you read through the posts here, you will see a lot of good experiences with the kGo.
Many people have a lot of problems with the eGo-T tank system. Some people like them at the beginning, but they usually discover that the eGo T mutes flavors, leaks and causes other problems, so they eventually give up on them and take them off.
2) You can get the kgo at this site, and they ship worldwide. They don't sell junk, so you won't find the eGo-T here.
KGO
3) I would recommend starting out with cartomizers. Do not use "dual coil" cartomizers. They need more power to work properly. For a 3.7V battery, the best resistance is 1.7ohm and 2.0ohm. For a good start, you should have:
1 x box of 5ea. 1.7ohm Smoketech "Ressurector" single coil cartomizers.
1 x box of 5ea. 2.ohm Smoketech or Boge single coil cartomizers.
1 or 2 ea. 2ohm atomizers to test juice before you fill a cartomizer with an unknown flavor.
minimun of 1 or 2 drip tips to use on cartomizer or atomizer, 510 size.
Juice of your choosing.
The kit will include cartomizers or atomizers. Buy extras to fill out the order so that you end up with the above. Cartomizers are disposable, so make sure you end up with at least 10. You can always try clearomizers and tanks and other fancy stuff later on. There is an endless variety. Just stick with cartomizers for now.
4) Yes, absolutely. Joytech has no monopoly on good e-cigs. The best e-cigs in the world are not Joytech.