so, im looking at stew mac and all these other sites trying to figure out which file(s) are the ones i need. the straight ones that have sort of an oval shaped file seem to be the cheapest, will this work or should i get one thats "hollow"?

i dont need it for any hard use, just going back and smoothing out the frets on mine and my friends' chinese guitars. trying to get out as cheap as possible, also.

any other suggestions?
Well i got this build on fine going, and my dad decided to do a little reading on what he needs fret wise and we discovered that there are a few files needed. When you say smooth out the frets, do you mean the tops are worn, or the fret sticks out over the neck on each side. If the tops are worn, you need a crowning file in the correct shape of the fret. If they stick out, then you can use a file to shave them down.
they tend to stick out over the edge. i can just use a normal file from my dads toolbox, but id rather have one the right size... "right tool for the right job" ya know.