A good solution is to pair up with locals who already know cultural ins and outs. "There is a basic level of trust with someone from the country," says Goff. "Also, there is a huge learning curve, not just technical but cultural. More is unspoken here in Mexico than written. You need the right help."

Patricia Watkins, librarian for Business Information Service and Resources at Thunderbird American Graduate School of International Management, advises studying not just culture, but traditions, transportation systems, communications (if you plug in your laptop, will it work?), and currency. Start with comprehensive guidebooks for maps, local courtesies, and basic medical needs. Find the nearest U.S. Embassy, and make sure your lawyer knows where you are.

Raising capital for a business overseas can be difficult. Capital markets in many countries are not developed, and raising U.S. capital for overseas ventures is tough. Many would-be foreign entrepreneurs end up self-financing or tapping government assistance. And remember the old business axiom: Starting a business always costs more than you initially expect.

Finally, don't forget to check out the economics and politics of your potential country. The best business opportunity in the world isn't worth it if the place is politically or economically unstable.