I have only started listening to anime music radio and various other songs on Youtube.

I came across a lot of songs from Doujin that are REALLY good.

Personally, I never played these kinds of games before so I don't know the production quality but I am really impressed with the music.

Ever heard of OCRemix (http://ocremix.org/)?

Some of the best fan-made videogame music on the Internet, there.

It would definitely be nice if some more mainstream music could incorporate the style, but I guess that will never happen :(

You may also like Dwelling of Duels.