I find the Hittites endlessly fascinating as well. We are learning more about them at an astonishing pace, partly because many of the archaeologists who used to work in Syria and Iraq in more peaceful times have moved into other countries like Turkey, Cyprus, Armenia, and Georgia.

General introductions: Warriors of Anatolia: A Concise History of the Hittites by Trevor Bryce, The Hittites and Their World by Billie Jean Collins, and (especially) the relatively comprehensive Hittites: An Anatolian Empire are the best choices for an introduction to the Hittites. Warriors of Anatolia is essentially an updated synthesis of two of Bryce's earlier books and is written in a very engaging style. It's noticeably more speculative than his other works, but Bryce does a pretty good job of noting when he's leaving the beaten path.

Detailed introductions: The Kingdom of the Hittites and Life and Society in the Hittite World by Trevor Bryce are more detailed introductions to Hittite history and society. The Kingdom of the Hittites is not without its weaknesses - in particular, it relies too heavily on texts at the expense of archaeology - but overall it is the best history of the Hittites available in English.

Hittite archaeology: I recommend Ancient Turkey by Antonio Sagona and Paul Zimansky, Early Turkey: An Introduction to the Archaeology of Anatolia from Prehistory Through the Lydian Period by Martha Sharp Joukowsky, and Insights Into Hittite History and Archaeology edited by Hermann Genz and Dirk Paul Mielke.

Hattusha Guide: A Day in the Hittite Capital is a pretty good overview of the best-known and most important Hittite site, and Seeher's Gods Carved in Stone: The Hittite Rock Sanctuary of Yazilikaya is very useful as well.

Hittite religion: The standard overview is the ponderous Geschichte der hethitischen Religion by Volkert Haas, but I recommend the much shorter and more approachable Religions of Asia Minor by Maciej Popko if you can find a find a copy once libraries reopen.

Hittite language: The Elements of Hittite by Theo van den Hout is the best learning grammar for Hittite. A Grammar of the Hittite Language by Craig Melchert and Harry Hoffner is more of a reference grammar than a learning grammar, but it may be preferable for those who prefer to learn Hittite in transliteration and don't care about cuneiform. Tischler's Hethitisches Handwörterbuch is the standard student dictionary, which is also available in French translation as Vocabulaire Hittite. For those who can't read French or German, there's the still incomplete Chicago Hittite Dictionary. Hittite grammar is surprisingly simple compared to other ancient Near Eastern languages like Akkadian or other ancient Indo-European languages like Sanskrit and Old Irish, and in my experience it takes students only about a semester before they're ready to start reading texts.

I have written several posts on the Hittites, in case you find any of those relevant or interesting.