For journals not included in the resources below, the best way to locate information on acceptance rates is to visit the journal website (in the Author Guidelines section) or contact the journal editor directly. Some societies will also publish acceptance rates for their journals on the society home page.
Journal rankings can be very controversial and eachresource has pros and cons to their use. Journal Citation Reportsand SCImago are the two largest and most heavily used tools. For publications not covered by these tools, you might want to check out Google Scholar Metrics.