East London-based music concert recommendation engine startup Songkick has raised $3.5 million of what PEHub says is a $4 million in first-round funding, led by Last.fm backer Index Ventures, and confirmed to us by co-founder Peter Smith. Songkick lists gigs, links to concert tickets from some 16 25 UK/US vendors and, through a media player plugin, learns listening preferences from which to make gig recommendations. It already got $15,000 from Y Combinator and what was reported to be around $1.1 million from Index’s Saul Klein and from Jeff Clavier. In a sense, Songkick focuses on just a sliver of the feature set of something like Last.fm – but, with live music proving to be just about the only part of the music biz left making money, it could be on to something.