20. The computer system of claim 17 , wherein initiating the addition comprises: providing, within a user interface used by the first administrator to administer the first page, a selector having an associated context that includes field types; receiving textual input that was entered into the selector on a client device; forming a result set by identifying field types matching the textual input; and providing the result set to the client device for display in visual association with the selector.
20. The computer system of claim 17 , wherein initiating the addition comprises: providing, within a user interface used by the first administrator to administer the first page, a selector having an associated context that includes field types; receiving textual input that was entered into the selector on a client device; forming a result set by identifying field types matching the textual input; and providing the result set to the client device for display in visual association with the selector. 21. The computer system of claim 20 , the computer program further comprising: instructions for determining whether the field types of the result set are associated with a page type of the first page; and instructions for ranking the field types of the result set based on the determination.