I'm currently working with XNA and Torgue X Builder (for 2D games).
To test them on my XBox, i had to get the XNA Creaters Club Abo, which is 49 for 4 month and 99 for 12 month.
I didn't have to buy a XBox Live Gold account, maybe that's just for sharing the games (which i didn't try yet).
XNA GameStudio is free to use and it's kinda easy to create games with it. The workflow is nice in programing and audio management, but of course you have no level or model editor.
The good thing is that you can script your game once and use it both for windows and xbox.
Torque X Builder is exactly like Torque Game Builder. The workflow is awesome and it's super easy to create games with it.
I really like the fact to test my games on the Xbox360, especially with the controller and it's features like vibration
Though i did no real game with it yet, i played around a lot, created normal movements, added audio, made two player modus (with 2 controller, no network yet) and some other stuff and its really fun.
I would suggest you to get the XNA GameStudio and try it by yourself for Windows only maybe, i think you don't have to pay for anything then.