You can read a lot of information on finding investors in the United States, but you know full well that Argentina is a totally different market, so you have to look there.
What about http://www.inversiones.gov.ar/, which looks like a government site about attracting investors? I found it by searching for "agencia desarrollo argentino" in Google. Look at the links there.
Look locally; you'll have way too many hurdles to jump if you try to sell not just your idea, your business plan and your team but also the idea of Argentina as well.
Tim Berry is the chairman of Eugene, Ore.-Palo Alto Software, which produces business-planning software. He founded Bplans.com and wrote The Plan-As-You-Go Business Plan, published by Entrepreneur Press. Berry is also a co-founder of HavePresence.com, a leader in a local angel-investment group and a judge of international business-plan competitions.