Listening to recordings is the next best thing to listening to live performances. I think your recording library says a great deal about how serious a musician you are. Listen to all styles, all genres, all instruments. You never know where inspiration will show up!
In the “SOLOS” section of this site I mentioned a list of solo recordings in the “Solos for the Student Trombonist”.
In the “EXCERPTS” section I mentioned tromboneexcerpts.org as a resource for specific trombone excerpts.
There is a wonderful resource compiled by Gerald Sloan called “Orchestral Recordings for Low Brass Players” that lists and annotates hundreds of recordings recommended by the top players in major orchestras. I have picked up many spectacular recordings I would not have known about otherwise.
Jazz artists will be coming soon in the “JAZZ” heading, which is next to be constructed.
I purchase recordings from wherever I can find them. I have had pretty good luck with amazon.com.