Before you request your file, read the law for your state. Even if your state doesn't require it, you should put your request to see your personnel file in writing. If you live in a state that does not have a specific law ensuring you access to your personnel records, all is not lost.
Originally, the disc in disc jockey referred to gramophone records, but now DJ is used as an all-encompassing term to describe someone who mixes recorded music from any sources, including cassettes, CDs, or digital audio files on a CDJ or laptop.
Mixxx is DJ mixing software created and maintained by the open source community. It's free, offers great basic capabilities, and supports around 30 external midi DJ controllers. It's where any aspiring DJ should start off, and it's good enough that you may never leave it--unless you're an FX junkie. To describe Mixxx is to describe just about any DJ software. Basically it mimics a two-turntable physical setup with two wave displays, two sets of controls, two digital turntables and a fader control.