I met my husband online, and immigrated to the US to marry him. So if you decide to go that route, I'll be happy to pass along what I remember of the process. It was about 7 years back, but I doubt a lot has changed. And there are a lot of resources online. There is indeed a ton of paperwork (but you can get it as PDFs to fill out), and they hit you up with a fee every step of the way, but it's broken up into chunks. The entire process took about 2 years for us, half of that before the marriage and half after.
My main tip for right now (aside from DON'T just run off and just get married like in the movies) is keep anything that could be considered a 'proof of relationship' - phone bills, plane ticket stubs, pictures of you together, love letters/cards. The more of that kind of stuff you have to prove that it's 'real', the easier a few steps are, and the less likely they are to call you in for more interviews and stuff. Also you'll need original copies of all relevent paperwork about your life - birth certificate (long form), divorce decrees, all that kind of stuff. I think you can (and will) send them copies in most of the forms, but I think you have to be able to provide originals on request. Can't remember exactly, but I still have a big folder somewhere with all the crap I had to send them organized by post-it tabs so I could find the stuff to copy that they kept asking for over and over. ;->