The site is called Elyonim veTachtonim. Here’s the description from the site:
Elyonim veTachtonim project web site. As of today the first version of the database is finally available on-line and:
- covers the Babylonian Talmud [BT];
- bases on the Soncino Babylonian Talmud (English) and Wikitext Talmud Bavli (Hebrew, Aramaic);
- distinguishes between three classes of entities: angels [ang], demons [dem] and ghosts [gho];
- (more or less) all the units involving dem of the BT are done; these with ang and gho are still in the stub form;
- distinguishes between six genres: biblical anecdote [bib], rabbinic anecdote [rab], cultic protocol [cult], pragmatic advice [prag], proverb [prov] and statement [stat];
- recognizes a number of entities and topics;
- covers all the attitude types.
I don’t know if the database is searchable (I couldn’t find a way to do that), but it can be downloaded in Excel format.
Sure it is searchable! Just click anywhere on the sheet (assuming you are on the web site) and press CTRL+F – this will call the simple Excel search menu. For anything more tricky though I would recommend downloading the database and running it offline.