Founts refer to sources of knowledge or information. There are several synonyms that serve the same purpose as founts. Some of these synonyms include: wellsprings, reservoirs, origins, springs, and roots. These words denote a place where one can draw information from. While the word "sources" could also be a synonym for founts, the latter has a more poetic ring to it. If you are trying to convey the idea of an inexhaustible source of knowledge, synonyms like fountains could be used. Ultimately, the synonym you use for founts depends on the context of your writing, but the aforementioned ones should steer you in the right direction.