9. A computer storage medium including instructions that, when executed by at least one processing unit, perform the following method: providing a registration document, wherein the registration document maintains at least a first registered resource object type and includes first contact information for a first provider of the first registered resource object type; receiving a registration of a second resource object type, wherein the registration of the second resource object type includes second contact information for a second provider of the second resource object type; editing the registration document to include the second registered resource object type and the second contact information for the second provider; receiving a request from a first wiki editor hosted by a first client computing device for a list of registered resource object types, wherein the resource object types comprise categories of wiki resources; sending to the first client computing device the list of resource object types including the first registered resource object type and the second registered resource object type; receiving a request for a list of options for the second registered resource object type; requesting the list of options for the second registered resource object type by accessing the registration document, obtaining the contact information for the provider of the second resource object type, and requesting the list options from the provider; sending to the first client computing device the list of options for the second resource object type; receiving first input text; acquiring a filtered list of options that contains only options for the second resource object type that include the first input text; receiving the filtered list of options; receiving a selection of one of the filtered options; and inserting a link to the selected filtered option in the text content.
9. A computer storage medium including instructions that, when executed by at least one processing unit, perform the following method: providing a registration document, wherein the registration document maintains at least a first registered resource object type and includes first contact information for a first provider of the first registered resource object type; receiving a registration of a second resource object type, wherein the registration of the second resource object type includes second contact information for a second provider of the second resource object type; editing the registration document to include the second registered resource object type and the second contact information for the second provider; receiving a request from a first wiki editor hosted by a first client computing device for a list of registered resource object types, wherein the resource object types comprise categories of wiki resources; sending to the first client computing device the list of resource object types including the first registered resource object type and the second registered resource object type; receiving a request for a list of options for the second registered resource object type; requesting the list of options for the second registered resource object type by accessing the registration document, obtaining the contact information for the provider of the second resource object type, and requesting the list options from the provider; sending to the first client computing device the list of options for the second resource object type; receiving first input text; acquiring a filtered list of options that contains only options for the second resource object type that include the first input text; receiving the filtered list of options; receiving a selection of one of the filtered options; and inserting a link to the selected filtered option in the text content. 11. The computer storage medium of claim 9 , wherein the first provider and the second provider comprise web servers hosted on different computing devices.