Clicking on the the green '+' at the start of each catalogue entry will reveal further information about the work in question -such as when it was meant to be performed, what the Epistle/Old Testament and Gospel readings were for the day in question and so on. A link to the full score for each cantata is also revealed when that '+' button is clicked. The full scores are the best editions that I could source which are believed to be out of copyright (or copyrighted with a permissive CreativeCommons license) in the UK at the time of writing. They may not be copyright-free in your country. Specifically, they are unlikely to be copyright-free in the USA, and if you are a citizen of the USA, you should not download them.
The catalogue is a work in progress and new works will be added to it as time and energy permits! Clicking on the name of that entry will take you to a page of translation, music excerpts and analysis.