L1 Revisiting US permanently

[tej16]

Hi,

I visited US last year on L1 Blanket visa, which is valid till Jan-2013 and came back after 2 months. Now I have got transferred permanently to US.
So can I go US on my existing visa or do I need to apply for new visa?
Do I need to get new petition?
What is the process for applying dependent visa for spouse?

Thanks