An information database in communication with an information application comprises {HEAD ~ a plurality} of {TAIL ~ marketplaces} and a plurality of listings respectively classified within the plurality of marketplaces 
of
An information database in communication with an information application comprises { HEAD ~ a plurality } of { TAIL ~ marketplaces } and a plurality of listings respectively classified within the plurality of marketplaces
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH