I have to disagree about posting tracks on a forum and getting forum members to give you feedback. The real reality is that a lot of music that is posted on forums is way below standard. End of Story. The problem you have is all the forum members are saying how great it is to be nice. Many forum members dont have the critical ear required to pick amazing music over ordinary music. Much of the music on forums even in our own songs forum here would not get to first base with a high end production library.
The best place to get feedback is from the libraries themselves. And TAXI is still a good source of feedback as well. They have screeners who know a lot about production music and how good it has to be and what the problems might be with your submissions.
The reality is if you produce an absolutely amazing cracker piece of music then TAXI and everyone else will fall over themselves to take you on. FACT. If your music is even just slightly shy of this then it will only get a warm reception. From anyone. The reason is the standard is very very high out there. A good idea is to really listen to the best guys doing library music and see what you are up against and I am telling you the bar is seriously high. What it means is if anyone is telling you that certain libraries or organisations like TAXI are not that great it really means their music is not that great either. Sorry to be so harsh but it is true.
I watched one of those TAXI pod casts about a guy who earns a six figure salary from doing just library music but as soon as the music came on it was like WOW! Beautiful writing, excellent melodies, chord progressions, musical arrangements, performances and production.
(And he was doing it all on an IMac on a little table in the corner of a room!!!) Don't let me put you off though. It is worth doing and this is a growth area for sure. You won't make it big as an artist in the normal mainstream but you have got a very real chance in the production music area. They are not hiring composers as much as they use to.
(I know because I am one!) They are using library tracks more and more. Don't copy what is out there either,
(listen to it though) you have got to come up with something completely original and fresh sounding. That is the challenge !