binsearch.info is a free search engine for nzb files... as far as what you need to load the nzb files in, try either http://www.newsbin.com/ or http://www.shemes.com/
http://www.binverse.com/ has a free trial although you need a CC to start it.
also try this thread:
http://www.nfohump.com/forum/viewtopic.php?t=55106
asus z170-A || core i5-6600K || geforce gtx 970 4gb || 16gb ddr4 ram || win10 || 1080p led samsung 27"