Where can i buy long screencables ans power cables?

Have a look here:

http://www.monoprice.com/home/index.asp

Power Cable? Just about any hardware/general store sells extension cords, you shouldn't have trouble with that one. lol

HDMI cables come in lengths up to 100ft at newegg.com, I'm sure 50ft+ can be found at a large number of electronic stores.

Mouse/Keyboard, once again all you need to do is buy USB extension cables, not sure how long they come. Maybe a wireless set up would work too.

Personally I think it would be cheaper/easier to replace the noisy fans in the computer so it's no longer noisy.

thanks. I build a new computer with goal of being quiet. my last pc where ok quiet. changed cpu fan, psu. but cabinet was not that good. then i bought a fractal design r3 expecting it to be really quiet, but it was not as i expected. same noiselevel as before, maybe abit more because of the case fans.

abit OT, but if the case fans is connected to MB can their speed be controlled with a program like speedfan? does most new MB support that?

EBAY

Yeah you should be able to control case fan speed from a program, and you can probably adjust fan speeds in the BIOS as well.