Spanish in South America

1. Are the Spanish accent in South American countries all different?
Say, if the two countries are neighbors - like Colombia and Venezuela - are the accents of the two countries kind of similar or noticeably different?

2. Argentina is relatively a young country. Is the Argentine accent uniform throughout the country?

3. Can Spanish speakers tell where the person is from by his/her accent?
I mean, can they detect wheter he/she is from Peru or Ecuador by his/her accent?

1. Yeah Colombia and Venezuela do have different accents.

2. Not just Argentina but all the countries in the Americas are young countries, but yes I'd say they have a uniform accent throughout the country.

3. Yes they can, and quite easily, just like a Canadian can detect when someone's from England, Ireland, etc.

http://en.wikipedia.org/wiki/Spanish_dialects_and_varieties