Customer database project in Filemaker Pro 8

I need help with some things in my clinets database wich I use FileMaker Pro 8 for. Some small fixes such as a script who can detect duplicate customers. Import a new list the right way. And if possible make a script wich can compare the name and adress with a phone directory on the web. Lets discus how far we can take it to make the work faster and more effective =)