That depends on why do you need to learn spanish.

If it is just to have regular conversations you could start to listen music, specially from mexican artist because the have a very light accent, but not traditional or folk music, at the beginning romantic or slow pop, then to pop and rock.

Some artist you could listen are:
Fernando Delgadillo
Edgar Oscerasky
Benny Ibarra De Llano
OV7 also knowed as Onda Vaselina (already dissolute)
Kabah (already dissolute, both OV7 and KABAH were pretty commercial music but good to learn bcz you can hear different voices and learn to pronounce)
Emmanuel
Yuri
RBD (not my favorite, totally bubble gum)
Kany Garcia (not mexican)
Miguel Bosé(not mexican but spanish)

But If what you need is learn to have bussines conversations you really need to get a course in some school or institute because in spanish there like 7 ways to name one thing and sometimes you learn to talk in slang that may not sound like slang for you but is not the right way to speak is you are making bussines and want to prove you prepare and reliable.

me i learn english(because normally i speak french)by watching anime and book,then i compare the text with my regular language…i also do the same with video games. but if you want to learn fast you can try read dictionary XD

Try with Spanish songs, like Mi Amor, La corazon, and hear spanish songs like que sera sera, guantamanera. You’ll enjoy and love it while learning. Try also spanish eyes.

The best way to learn Spanish is to hang out with people who are fluent in Spanish and tell them to only speak Spanish to you. After a while you will start to understand it and it will come to you…all it takes is dedication and a lot of patience.

spanish class

Well the way i learned is by using Rosetta Stone. It is very fast and very good. Plus i took a formal class in high school

Rosetta Stone and to live or visit a Spanish Speaking country for a long time. I recommend Spain.

A great way to learn spanish is to enroll yourself at a local college and take a spanish class. Or if you have the means the rosetta stone software is a great way to learn also.

reading spanish newspapers daily. watching spanish news daily.

Live somewhere where you’re forced to speak Spanish. In 3 months you could be fluent.