What about incorporating Google AutoComplete on adress fields? 
And, more important, would it be possible to have some co-operation with a "data-mining" company so that if I would like to add a company then it can auto-search for information. Lets say i would like to add Statoil ASA in Norway, then searching for Statoil would find it and add fields such as ORG/VAT number, address, contact persons etc. Such information is public in Norway at least, with www.brreg.no