To have a good basic overview of epistemological problems read: Descartes Mediation, Spinoza's On the Improvement of The Understanding and Ethics, Leibniz's Mo

To have a good basic overview of epistemological problems read: Descartes Mediation, Spinoza's On the Improvement of The Understanding and Ethics, Leibniz's Monadology, Kant's three critiques, Hegel's Phenomenology and Logic, Heidegger's Being and Time. I would stay away from analytic philosophy, if you are not an US based academic.