You can call a toll-free number from abroad, though sometimes you will incur international calling fees. Most toll-free numbers are intended only for customers inside the United States and Canada.
Normal telephone calls incur a fee for the caller, not for the receiver. However, certain toll-free numbers are set up to incur the fees for the receiver, usually to encourage people to call without worrying about charges. For international calls, however, fees are much larger than those for domestic calls, and recipients are unwilling to pay these higher fees. There is a certain category of International Freephone numbers that allow callers from certain countries, mostly wealthier ones, to make toll-free calls. These numbers are set up to have a country code of 800, unlike American 800 numbers, which have a country code of 1.