Thank you very much for the advice master. My nails are shorter and that really improved my sound and volume. I'm also playing harder, but here's the problem.
When I'm playing Leo Brouwer's study no.1 (from the "6 Estudios Simples"), I need to achieve some fortes and fortissimos marcato. Since the study is kinda powerful (I'm too lazy to think of a better adjective

) , that really needs to get the all the sound out of my guitar, but I'm making it sound ugly. Regarding this, my new teacher (I'm taking classes with her for a couple of months) told me to practice playing harder everytime I play, but to play Brouwer's study thinking about the music, because I was getting louder but the sound was getting poorer.
Bottom Line: do you know any studies that I can play to get louder volume? Specially with the thumb.
I'll be going on a short 1 week vacation the first week of January. After that I'll try to post in youtube some videos of myself playing.
Thank you very much master, have a great 2008.