The French, Dutch, and British Lexicon Projects provide reaction-time data from lexical decision studies with large samples of words and non-words.
Ferrand, L., New, B., Brysbaert, M., Keuleers, E., Bonin, P., Méot, A., Augustinova, M. & Pallier, C. (2010). The French Lexicon Project: Lexical decision data for 38,840 French words and 38,840 pseudowords. Behavior Research Methods 42 (2), 488–496.
Keuleers, E., Diependaele, K. & Brysbaert, M. (2010). Practice effects in large-scale visual word recognition studies: A lexical decision study on 14,000 Dutch mono-and disyllabic words and nonwords. Frontiers in Psychology 1.
Keuleers, E., Lacey, P., Rastle, K. & Brysbaert, M. (2012). The British Lexicon Project: Lexical decision data for 28,730 monosyllabic and disyllabic English words. Behavior Research Methods 44 (1), 287–304.
Further projects can be found on a list of word megastudies with links to data (if available) , compiled 2019. This list is linked to a list of databases.