InfoPath Dev

so I need to create a contact list of external clients. I created a contact list in sharepoint but how do I keep distribution lists centrally located in sharepoint?

what exactly do you mean by centrally located in sharepoint.

just give permissions to everyone to read that list

You can't.  They will only be visible within the same site collection, so if you have multiple site collections, you would have to copy the list and the data to each one and keep them manually updated.

I suppose an alternative would be an external DB of customers that you connect to with the BDC (if you have MOSS Enterprise), and then expose that data in web parts to all of SharePoint.

Btw, what is the question's relevance to InfoPath?