More specifically, where can I find books written in our disciplic succession?
I'm thinking about, in the future, I may want to read other commentaries on various scriptures. Like Bhaktisiddhanta Sarasvati Thakura's commentary on Caitanya Caritamrta.
I should mention I've already looked at sites like exoticindia.com, but they are quite pricey.
Do you mean English translation of Gosvami books? So far most of them were translated by Kusakratha P. They were printed in limited runs and can be found in some temple libraries. Some can be downloaded here: http://vedicilluminations.com/kusakratha/index.htm
BBT (store.krishna.com) and Isvara P., Vrindavan (touchstonemedia.com) are other major publishers, with price level similar to exoticindia, since they cater mainly to Western devotees.
BSST commentary on CC isn't available in English yet, afaik.