Pinker, Steven - Author of The Language Instinct and Words and Rules (Formerly at MIT, now at Harvard) - http://pinker.wjh.harvard.edu/
MacWhinney, Brian - CHILDES database, psycholinguistic tools and methods, language learning and processing (Carnegie Mellon University, USA) - http://psyling.psy.cmu.edu/Brian/
Avrutin, Sergey - Language acquisition, language impairment and theoretical linguistics (Utrecht University, The Netherlands) - http://www.let.uu.nl/~sergey.avrutin/personal/