Below are recordings for the services of the High Holy Days. Please note: these are recordings designed to help service leaders for small minyanim for the 2020 High Holy Days. They are relatively easy and unadorned so that they can be learned quickly. They are also truncated services leaving out anything that is not required to be done for the service (including piyyutim).
If you are a skilled service leader and wish to use more ornate nusach or different melodies, by all means do so. And if you would like to add things back in, you certainly may. However, please keep in mind that the truncation of these services is not just for ease of learning but also to minimize the amount of time that minyanim need to spend together. Safety is paramount and you should do what works best for your minyan.
A few assumptions have been made here:
Sheet music is available for many sections of these services. For nusach and some congregational melodies, sheet music is available in these books by Hazzan Pinchas Spiro:
Marsha Nagorsky has transcribed a number of the congregational tunes, so contact her if you need sheet music for those sections.