Music is something that can help you out in any kind of situation and it also helps you focus more. There are so many studies out there which show certain types of music helps you increase your productivity and helps you focus more.
I have found a certain type of music which always helps in general and have put up a few links for it to be just a click away.
So here it goes...
Nature Sounds - Nature Sounds make you feel more alive and fresh and that helps you concentrate more. Certain people have the tendency to visualize the moment they hear something, so if you are around such kind of sounds you start feeling more active or even relaxed if that is what you need.
Classical Music - Classical music is always soothing to the soul! No matter what and when you hear it always touches you. There are a lot of studies which prove classical music to be the most effective.
Songs/Music Without Lyrics - This one is important because if your music has words to it you are going to get distracted and would want to sing along. So go for the ones with no lyrics that will help you focus more.
Instrumental Music - I truly love instrumentals. It gives you the best of both worlds. You get to listen to your favorite songs in the music form and get to enjoy it as well while concentrating without getting distracted!