There really isn't much of a difference between manufacturers when it comes to cold cathodes. If you want it to blink to music or something then go for one of those, if not just get the cheapest one you can find. I got a 12" uv cathode for about $5 or so that is about as generic as you can get and it has been working fine for over a year.
As for placement, if you have a window just put a 12" light on the bottom of the case right up against the window side of the case. That usually turns out looking ok. If you have a giant nVidia card that eclipses the upper half of your case just put another 4-12" cathode in the top of the case.