I'm aware that there are many phonological rules, but I don't have a big picture of how many there are and where I can find them. Is there a book, a review paper, a website, or any source that have a collection of them? I read 'Understanding Phonology' and there are some. Are there many more?
From the comments, it seems that you don't yet have a firm grasp of what a "rule" is, so my recommendation is based on getting a better grasp of that concept. Rules and constraints have gotten mixed up in phonology so that it's hard to tell what a rule is, especially because rule theory toyed with the concept of "constraint" to the point that the theory sort of self-destructed.
Chomsky & Halle (1968) The sound pattern of English is the classic "defining" work in the theory of phonological rules. That work has many rules, but they are only from English and frankly it is dubious that English has such rules (mostly, it describes marginal word relations like cone ~ conic which are about how English orthography is interpreted). There are some text books that present analyses within that general theory, including Hyman Phonology: Theory and analysis, Kenstowicz & Kisseberth Generative phonology: Description and theory, and Odden Introducing phonology. The first edition of Understanding phonology is a hybrid, being halfway in classical rule-based tradition. The introduction of autosegmental phonology in 1976 complicated things, and resulted in the introduction of factors outside of rules, such as "The Obligatory Contour Principle" which is a supposed principle of grammar that regulates what rules do. Understanding phonology is a mix of the two approaches. Kenstowicz Phonology in generative grammar is also somewhat mixed, and is also much more extensive in terms of data coverage: I would say that that is the best textbook that attempts to convey ideas as to how rules in autosegmental theory are formalized, and any shortcomings are because the field had not sorted out how to write rules in the new model. I honestly do not know how people address the question of constraint-statement in introductory phonology classes that assume OT. Perhaps the answer is that they do not, after all, Hayes in his Introductory phonology offers conventional rule statements, even though he is an OT enthusiast.
In the theory of rules, there isn't a list of rules, any more than there is a list of equations in mathematics. The theory (there is more than one) allows certain things to be rules, and every theory allows zillions of things. Certain things are fairly common, which is the domain of typology – there is a chapter on typology in Introducing phonology. What the textbooks above focus on is the methodology of analyzing data into rules, so naturally you will get examples of rules in learning how to make your own.