Yes.

A language is a bunch of symbols. You communicate in a language by expressing your vibration within the bounds of the language. Some languages work better than others for different purposes. Music works really well for emotion, the same way that facial expression and dance does- and unlike mathematics, computer code or dry speech. Because music is so efficient at communicating emotion, it is the easiest way for most people to bring up a certain mood. Everyone knows that mood affects behavior, although they may not know it also affects circumstances, so, to some extent, everyone who listens to music is using it to manifest.

In the more narrow sense of your question, you are asking if anyone is using music deliberately as a manifestation tool. Abraham recommends individually chosen pieces as an energizing tool. When I write songs I write them to reflect a certain mood I am having- mostly feeling hot, cool, friendly, warm and amazing all at the same time. The style that does that best for me is electronic funk music. Then there is the music in Bashar's holotope experiences, Tom Kenyon's spiritual music, and, probably the pioneer of expressing celestial states using earthly musical tools, Iasos.

The reason it is only so popular is that unless you are a musician you can only chose states that someone else has already expressed for you, which can be a bit unwieldy. It is the same limitation as manifestation tapes or affirmation recordings- someone else thinks these affirmations are great, but do you? And do they mean the same thing? They eem to me to be way too static for my manifestations- I spend a lot of time fine-tuning my Haipule, a combination of imaginations, affirmation, breath and symbolic action in a ritual structure. If I use canned stuff or even just old versions of my affirmations, they never quite manage to tickle my excitement and vibration like fresh stuff I imagine straight from the ether in endless variants until I discover the perfect version from the time. The artistry is lost with recordings as far as my daily practice is concerned.

Imagining sound, on the other hand, is a really, really good idea- imagine a melody that represents the feeling you want, maybe even expand it to a piece, and use it to reach the vibration you want. And, if you like, learn how to play it and share it with others, so they have examples they can use for their own imagining.

That's how I would do it- imagine music.