1. A computer implemented method for accessing information from a plurality of searchable information sources, comprising: analyzing a search query to determine subject matter of the query; and selecting a subset of information sources from the plurality of information sources based upon the subject matter of the query; wherein the subject matter of the query is derived by comparing the search query against a knowledge-base, the knowledge base including a taxonomy of subject matters and a set of terms for at least some of the respective subject matters, the set of terms representing information likely to be found in the respective subject matters, and wherein comparing includes comparing at least portions of the search query against the sets of terms in the knowledge base to determine the respective subject matters of matching terms.
5. The computer implemented method of claim 1 , further comprising building the knowledge base, wherein building includes: defining the taxonomy of subject matters; for at least some of the subject matters in the taxonomy, providing at least one example document that represents content typically found for the respective subject matter; generating a set of terms from the example document; and linking the set of terms to the respective subject matter.