OK, this is a gray (or is it grey?) area. You can purchase complete databases that provide city names, alternate spellings, etc. for each country, but then do you use the 'english' or the 'native' name for a particular city? Is it that important in this forum? What level of accuracy is needed? If ultra-accuracy is needed, then you will need to buy address verification software (which verifies down to the apartment number), if it is a digital and informal forum, perhaps an email address should be the minimum, and a BASIC geographical point of referrence should be more than enough.
I am surprised that so much 'ink' has been spewed over this topic....
-R!
Ricardo A. Parodi
eSolar, Inc.