I once heard that the ten plagues were supposed to reveal how God rules over everything. Does anyone have a source that explains this in detail: how each plagues revealed one aspect of this?
There are many sources that deal with the plagues and their meaning as well as each plague individually, many of which are found in some of the different haggadahs that have been published. Rabbi Shimson Rafael Hirsch, in his commentary on Parshas Vaera (7:15) goes into detail on the subject. He also goes into more detail with each plague pointing out individual elements of that plague (such as the hail stopping in mid air as one example).
I speak of the plague of frogs at Vaeirah - The original "Green Line" which deals with this subject.
Since each plague and the entire Yetzias Mitzrayim are complex and reveal multitudes of insights, it is impossible to have one central source. Another good source is Rabbi Sorottzkin Oznayim Latorah
Rav Yehuda made a siman for the 10 makkas D’tzach ,A’dash ,B’achav three distinct classes. The Kli Yakar explains why three separate classes. The מהרי"א explains that Paroh argued on three points 1)He didn’t believe in Hashem 2) Even if Hashem existed he created the world but doesn’t get involved. 3) He believed even if Hashem is involved he can’t change nature.,(he also did not believe in a one and only God).
The Kli Yakar explains that this siman that Rav Yehuda made for the makkas answers the three questions Pharaoh had. The first set of makkas(D’Tzach) the first makka ,the passuk says with this you will know I am Hashem. The first three makkas Showed that Hashem exists and furthermore pharaohs false god the water which he worshipped was really nothing at all and it even turned into blood. At the end of this set of makkas which was makka kinim(lice) the sorcerers answered Etzbah Elokim(this is the finger of Hashem) so the first set proved parohs first question wrong.
The Second set A’dash by oirev the first makka of the set Hashem said you will know that I am Hashem and I am B’kerev Ha’aretz(dwells in the earth). This set was to prove Pharaohs second question. These Makkas Hashem distinguished between the Rashim and the Tzaddikim and this proves that Hashem didn’t abandon the humans rather he still is B’kerev Ha’aratz. These makkas, Hashem distinguished between the Jews and the mitzrim it would stop by the borders between Jew and Egyptian.
The Third set B’achav came to answers pharaohs third and final question. The first makka of this set is Barad and the passuk says you will know that there is none like me in the whole land (world). Paraoh believed in many false gods the sun the mazalas(stars) especially the sign of Nissan the lamb, he believed he gained strength from these things. So Barad blocked the sun there was no sun by makka arbeh and by chosech as well. By makkas Bechoros it was at night, and the mazal for the month is the bechor of all mazalos. All the powers which pharaoh believed in at the end really turned against him.
The Ramban in Parshas Bo, Chapter 13, Verse 16 on "and Totafos between your eyes" discusses how the Plagues demonstrate that Hashem is the creator, knows all, and oversees and is all powerful. It is a worthwhile and important Ramban to go through.