I have a "Katie" artist edition porcelain doll from Georgetown Collections.
I would like to know what she is worth and where could I sell her.

You could consider a website like e-bay to sell it. Not sure what they are really worth; but I did find one listed.. hope it helps
GEORGETOWN "KATIE" GIFTS OF ENDEARMENT PORC. DOLL NRFB - eBay (item 330336586150 end time Jun-14-09 11:20:09 PDT)