There are so, so, so many songs for you to discover! Welcome to the fandom. :) the producers that use Miku (people who use Miku's voicebank to create their own music) live all over the world, therefore making a great amount of different genres in the fandom.
Here are some of my favorites you can search up on Youtube to get you started!
-Last Strobe:
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-Chameleon:
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-Rainy Reincarnation:
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-Initiation:
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-Rain Sound:
link
-Sobani Itekuretane:
link
-Meteor:
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-Shooting Star Prologue:
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-Experience Point:
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-Freely Tomorrow:
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-Blank:
link
-Top Secret:
link
-White Letter:
link
-Letters:
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-Wingless Angel:
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-Stomp the Enemy:
link
-Reverse Rainbow:
link
Remember, there are many, many, many other vocaloids out there besides Miku- each software has a unique voice to enjoy! Try the vocaloids IA, Lily, Kagamine Rin, Yuzuki Yukari, VY2, Megurine Luka, and Aoki Lapis- those are my favorites! c: The Vocaloid wiki has a complete list of all of the virtual singers: here is the website! You may have to do just a little bit of digging:
link
I hope you find music you enjoy. Use this to get you started!