There is post earnings announcement drift though. It takes big money days and weeks to build a position. Google it as there are several academic papers on it.
$50/month for one publicly available dataset? we're not talking about some alpha generating alternative dataset here. for that i'd pay thousands if not hundreds of thousands/month
https://www.quandl.com/databases/SF1/documentation?anchor=exception-handling These guys provide a large data set (sure public information) for a low cost of $29, as @sle mentioned, quandl makes it super convenient. If you have a some basic programming knowledge, scrape this site https://stockrow.com/AAPL its free. You could also spend 1 day to learn the basic commands in R/Python and just use a package that scrapes yahoo (also free). You rarely find alpha generating data sets. It usually comes from raw public information which you then transform in house to find alpha.