If you are talking of Indian Stock Market then these are the list of top vendors below. Viratech Global Data Feeds True Data India Equal Solution Many more are there but these are market leaders. All these vendors are provide free trials. Best solution is to check their prices and demo and decide yourself
Dear jharmon, i am using free data from nseindia.com by downloading bhavcopy every day as i am a newbie . But this is bit rigorous and then convert in to amibroker by importing csv files. Only problem is if i need to check all symbols, this is really a hectic process.