I don't know what brand/model should i buy..
:please help me~

do you mean pedals? if so, then it's probably best to go and try out a few for yourself. it's all preference. i personally use korg and digitech.

Boss is a really popular brand, very durable, and never dies lollll. sound is excellent. one of the best and most trustworthy brands. their pedals are like made of metal haha so when u pick them up, ull know its solid, ull know its trust worthy...

right now i have a BOSS MT-2, its still as good as new, i dropped it alot of times stomped on it alot, never dies. i also have a Line 6 Floor pod which is a multi-fx pedal... some brands' pedals die out tho

cool, i'm looking for them too! probably a multi-effects pedal... i'm eyeing a Digitech one, the Boss ones are kinda expensive

There are wayyyyyy too many brands out there to list - do what Zenaku says and go to your local music store and try out as many of them as you can. Pick the one that fits your budget and also sounds good to your ears. I have a preference for Digitech pedals as well as BOSS. Line 6 is also very popular as well but I have never really warmed up to that brand.

Personally I'd want to try out a Keeley mod one of these days - some of the things done to those pedals are nuts =O