I think South American bonds may be speculative, but the returns
seem to be worth the risk. Where can one find detailed information and
where can one purchase these bonds online.

<a href="http://www.bradynet.com">Bradynet.com</a> is a good source
for information.  Note that the coupon (interest payment) is just one
factor to watch when evaluating the risk relative to the return. 
Inflation, devaluations, and even government default on bond payments
is common, and investments in these markets are not for the faint of
heart.

That said, if you do want to be in this market, a mutual fund is
probably the best way to go for a small investor.  You can diversify
among several countries (so if any one country tanks you will not see
a total loss) more cost-effectively than trying to do so on your own.

Good luck.