Music and radio is a highly competitive sector and being able to demonstrate that you have relevant work experience will be a great advantage. Building up a portfolio of work that shows your skills and experience is also important.
You could contact local promoters or record labels to see if they can offer work experience by sending a speculative application. Check Wired Sussex's directory for more local organisations involved with music
You could contact local radio stations to see if they can offer work experience by sending a speculative application