Chipping any console is illegal so your not going to find many stores willing to do it. I got mine chipped at a chinese food store that also sold imported video games. Kinda worrying leaving my PS2 overnight at a store run by people that barely spoke any English but thankfully they came through and I have actually become a local there since.

I would really advise you not to do it yourself. Its actually more expensive buying all the tools yourself and theres no trial and error. If you screw up its a 95% chance you've broken your PS2 for good.