If i want to use an audio and/or video recording of a live event with comercial purposes, who are the parties involved that i need to contact?
I assume that you mean something in the nature of a music or dramatic performance.
In that case, you need to contact the people who hold copyrights with respect to that performance.
In the case of a music group performing original material, you would ordinarily contact the music group's manager.
In the case of a dramatic performance involving original material, you would ordinarily conduct the performance's producer.
If the music group or dramatic performance was of someone else's music or script, under license, you would also need to get permission from the holder of the copyright to the underlying song or script, which could be determined from the registrar of copyrights or from the manager or producer of the work who had to contact that person to obtain a license to perform it.