You don't need to pay to become fluent in Spanish, and you don't need to buy a course.
But, there is no such thing as a free lunch, and Spanish courses used will help.
Products and courses are just tools around which you can structure your learning, but there is no perfect course.
Everyone is different, and to make efficient progress it is up to you to take charge of your learning.
I have used different courses and products while learning Spanish, although nowadays I primarily talk to friends who I found on My language exchange .
This doesn't mean I am perfect, but that I have reached a level that I am comfortable with.
Free online resources like Duolingo and Memrise are well known and widely used.
These are fun ways to pass some time, but they are better used in addition to other resources if you really want to learn Spanish.
If you like physical books, I've always enjoyed the Teach Yourself courses, and (unfashionably) consider that buying a decent Spanish Grammar is essential.
The teach yourself courses are not perfect, but you can use the structure as a framework to your own learning.
Personally, where possible, nowadays, I'd always start with an Assimil language course. I have had a love/hate relationship with these courses, but more and more they suit my learning style. I periodically write about Assimil on my Blog.
The conversational sentences and Spanish phrases on Surface languages are also useful starting points.
You have to listen, and listen a lot in order to understand, and podcasts are a great way to do that.
Spanishpod101 has literally hundreds of podcasts with transcriptions (among other features) so you can walk and learn, clean and learn, eat breakfast and learn during your spare time.
In fact, that is (almost exclusively) what I do to learn languages. I read and understand a transcript, and then listen repeatedly during the day when I am walking my dog, walking to work, cooking and so on ...
Once you reach an intermediate level of Spanish, one of the biggest hurdles to overcome is comprehension.
If you want to improve comprehension, have a look at Unlimited Spanish. The site includes free and paid resources. I haven't used the courses but there is a weekly podcast along with transcripts spoken at a speed suitable for intermediate language learners.
Spanishpod101 has podcasts aimed at different levels of comprehension, and spoken at different speeds.
I'd use a combination of both, unlimited Spanish to accustom yourself to spoken Spanish and grammatical structures, interspersed with Spanishpod101 for variety and speed.
News is slow Spanish is just that. The news spoken slowly. I subscribed to and used the French version for a while, but felt that the lack of 'proper' conversation was a negative.
It may be for you if you like the news. In the end, it didn't hold my interest.
Besos,
Moonface