Dealing with compositional challenges: How to?

[Ronito]

So here's the dealio. I solely compose for the classical guitar, sometimes I'll go out and include a flute or other instrument, but it's always in a very classical style.

One of my best friends is working on a project and asked me to write the music for it. He's my best friend, I can't likely say no, and I do have experience. But here's where it gets sorta sticky. The pieces required would be vastly different from what I typically write, we're talking Bossa Novas, Spanish, "beach music",Hard Rock, Country, Piano bar, possibly techno, celtic, and lounge.

I'm really excited for the challenge, as I think it would be a great learning experience. Problem is that I was only trained and only ever wrote in classical styles. How do I best branch out and write in these new styles, that I've heard before but never wrote in?

[Piano]

If you had all the time in the world, the best thing would be to make it as authentic as possible, going to concerts, listening to albums by renowned artists. However, you won't have all the time in the world so the best thing to do is to buy compilation CDs of the various styles and listen to them attentively and copy down salient characteristics (chord progs, melodic and rhythmic styles, etc.). Copying is very important as it allows you to know exactly what they do, then you'll be able to put your own spin on it. Good luck. :)