Leave it to my excellent readers, in this case Michael Gordon, to do my research for me. Michael directs those interested in foreign stocks, or more specifically the American Depositary Receipts that represent them, to these two sites:
This one, from Bank of New York, has an easily accessed directory of every ADR you’ll ever need, or at least all the ones I could think of. And when you scroll to the right, you find out where it’s traded, what its “CUSIP” number is (so your broker can be sure he’s buying you the right thing), and the ratio of underlying foreign shares to each ADR.
This one, from JP Morgan, is less comprehensive in terms of the ADRs, unless I missed something, but offers very interesting global maps and market information that allow you to “drill down” by region and industry and so forth.
The Bank of New York site is only interesting if you’re checking out a specific security. (And then it’s very helpful.) The JP Morgan site might be worth a look even if you just want to remember where Thailand IS, exactly, and how its stock market has been doing.