Most of the people I met, were from either business or frontend (UI design) background. I only met handful of data-mining/hadoop guys. The ones with I talked to were either happy about their current jobs or they already have some project going on in the part-time (with no commercial interest), so they can't commit to join startup.

So where do I find backend hackers who are passionate about data-mining, information retrieval, hadoop, etc. and are entrepreneurial and want to start a startup? And how shall I get them on the board? Please advice.