Here are some favorites from Process Type Foundry, who has a small but high quality catalog. I already own a couple of them—Bryant and Locator—but I’d love to have their whole library eventually. One of my favorite features of their site is where they show examples of each typeface in use. Definitely helps you get a better feel for how it would work in various applications.
Courtney is the founder of Design Work Life and Seamless Creative, a small design studio she runs with her husband Brian. She now splits her time between developing brand identities for small businesses and soaking up (and passing along) as much inspiration as she possibly can.