Pozar has a book that's a pretty good survey of a lot that went into this:
https://www.amazon.com/Microwave-Rf-Design-Wireless-Systems/dp/0471322822
It covers the linear approximation of PLL design, though it's only a starting point as it gets a lot more technical (and empirical) when you build one. It also covers oscillators, though my implementation was nothing fancy; a common emitter topology voltage divider biased BJT Colpitts oscillator with tunable varactor diodes and a common collector output buffer stage.
I also viewed this document here to gain some more intuition:
http://rfic.eecs.berkeley.edu/ee242/pdf/Module_7_3_PLL.pdf
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Note that this explores digital phase frequency detectors whereas I just used a mixer.
This'll also get you into the weeds:
https://www.ti.com/lit/an/swra029/swra029.pdf?ts=1642870097796
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That should do it. I'll see about the blog. Seems like it would be fun to do if I have time!