There ARE lots of sites. Lots and lots. Too many, perhaps!
One of the best methods is to hire a teacher for a while. No, not me! I'm booked up, and off on holiday! But there are plenty of teachers who can help assess your level, and assess which sites might be best for you.
It's good to have a course book. And to work through it with a teacher.
So look on italki for a teacher, or an informal tutor, who can help you get the best from your websites and books.
I'm learning Portuguese, and though I have books and websites, I still need a REAL PERSON to talk to.