Well, that's nice and all, but the advice really amounts to: be clever. Excellent advice in any endeavor, I should say.
Scott did miss one aspect of online searching. Just about any name will turn up on Wikipedia. And that lovely source will give not only alternate spellings but historical spellings. It's even better for place names because it will yield the old Roman name or Germanic name for that town or mountain. Very handy!
Another angle, for name-mungers: find maps in other languages. You might be surprised to learn the French name for the English Channel -- you can bet they don't call it the "English" Channel! It's great fun finding Italian names for mountains in Poland, or French names for a Hungarian river.