Help needed on US applications

Hello
I know this is a site for US people in the UK.
I am going to marry my US girlfriend in July (very excited) I want to get a visa/greencard for me to live and work in the US.
I have looked at the US gov pages and its not 100% clear on what I should be filling out.  Does anybody know what we need to fill out to start the process?
We have already had an interview with the UK people in Chicago, so we know how to get her here, but me there with a work visa is what we need to find out.  Is there a difference between a work visa and a greencard once I am married to her?

Any help would be great.
Cheers
p

Is there a difference between a work visa and a greencard once I am married to her?

A lot of people mistakenly believe that green cards are nothing more than work permits. While a green card does give you the right to work legally in the U.S. where and when you wish, that is just one of its features. Identifying the holder as a permanent resident of the U.S. is its main function.

The counterpart in the UK is Indefinite Leave to Remain, or ILR.