It's a bit too expensive to have both Japanese AND English manga at the same time, so if scanlations are available, download them - except that scanlations are sometimes inaccurate. Another alternative is: buy the original manga in Japanese and have a dictionary handy to help you when you come across words you've never heard of. It's an expensive method, though. Where I come from subbed manga is at least 4 times cheaper than the originals.
Also, because not everyone has access to Japanese TV channels, there is always Youtube - where you can watch J-dramas, interviews, anime, etc. Even better if you know a Japanese person or are planning to go to Japan for a student exchange - actually conversing will help you more than anything else in the world; I know because it worked for me, and probably the only reason why my Japanese didn't improve as much as it could have while I was in Nagoya is that I was just to shy to talk.
Ganbatte ne, shinopious, and anyone else who's about to immerse him/herself in the language!