Well, in Korean shopping, there's a lot of this to buy, so I've compacted as much as that into one thread...
First, you need to know how to say:
실례합니다, 이거 얼마에요? [sheel-yeh-haam-nee-dah, ee-goh ohl-maa-eh-yo?] Excuse me, how much is this? Preferably pointing to the object that you are asking...