You can get them at a arts n craft or hobby store, like Michael's, Hungates, Paul's, it's cheap, I think $2+.

Great! That doesn't sound so bad! Now, where could I find the ink? Is it a special kind of ink? Would you recommend me a brand and a place to get it? Thanks man!

Hey welcome aboard man! Basically it's a technique used on gundam models. You get a brush pen(like a sakura micron brush pen), go over the area like one with panel lines, and generously brush some ink on. Then after a few seconds, or a minute, use a napkin to wipe off the ink. The ink should stay in the lines, and also have a weathered look around the edges. I did this on my Classics Jetfire as well as other Transformers figures and it makes a WORLD of difference. Just make sure to never use a sharpie as I learned the hard way that it will turn purple later on.

Dude! I saw your comment on the post about the "Yamato 1/60 VF-1J Hikaru Weathering Version" You were talking about knowing how to obtain very similar results using "one of the cheapest art supplies [you] have ever come across, and a napkin" I would like to know more about this. Could you tell me more about it? I am very interested. Thanks man!