Populate a contact lookup field based on selection of a PickList

Populate a contact lookup field based on selection of a PickList

Hello,

I know that i can setup a field dependency to auto select items from one picklist to another, but what we would like to be able to do is to select a District picklist field that contains a listing of cities and then populate a contact lookup field withing the lead with the correct person.  

is this doable? and if it takes coding help would be appreciated!

Thanks,

Rob