1. A computer readable medium including executable instructions which, when executed, manage information by: creating a plurality of information sources, each information source comprising a metadata definition document (MDD) having a uniform representation of metadata and including full-text search data (FTSData), wherein each information source can be linked to an underlying information source having a representative file format and used to provide additional content for use in searching and indexing operations; using a schema to define the MDD for each information source, the schema including a FTSData element to specify FTSData, asset and content elements to identify a linked underlying information source, and a queries element to identify query to underlying information source mappings; calling an intermediate handler to extract metadata and FTSData from the plurality of information sources, the intermediate handler to return the metadata and FTSData from each information source based in part on operating modes including: a first operating mode to append FTSData of each information source with FTSData of a corresponding linked underlying information source and provide a union of metadata from each information source and the corresponding linked underlying information source, including ignoring the metadata of linked underlying information sources for conflicts of first metadata types; a second operating mode to append FTSData of each information source with FTSData of the corresponding linked underlying information source and provide a union of metadata from each information source and the corresponding linked underlying information source, including ignoring the metadata of the information sources for conflicts of the first metadata types; a third operating mode to return FTSData of each information source and provide a union of metadata from each information source and the corresponding linked underlying information source, including ignoring the metadata of the linked underlying information sources for conflicts of the first metadata types and second metadata types; and, a fourth operating mode to return FTSData of each linked underlying information source and provide a union of metadata from each information source and the corresponding linked underlying information source, including ignoring the metadata of the information sources for conflicts of the first metadata types and the second metadata types; invoking a registered handler to extract metadata and other information from each linked underlying information source; and, using the metadata and FTSData as part of the indexing and searching operations.