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