Hi Vic01,
I'd suggest creating a custom autotext or building block entry for each doctor, perhaps containing everything from their address through to the "Dear Dr xxxx,". Then, rather than even having to type the doctor's name, it becomes a simple matter of inputting the relevant keyboard shortcut or choosing the right building block for the occasion. With either method, there is no programming involved and no links to Excel etc. to maintain.
To see how to create autotext/custom building block entries, go to:
http://gregmaxey.com/word_tip_pages/..._autotext.html
See also:
http://word.mvps.org/FAQs/Customization/AutoText.htm