On holiday recently I was surfing and discovered some recordings that can be played on the Internet by anyone. Some sadly some still need a password issued by an educational institution to listen to them. Maybe one day the will offer recordings of more interest to us Radio enthusiasts.
Having said that I found the sound effects of weather, also local accents and dialects, plus bird song and folk music of interest. Have a play around yourselves. Contact the British Library and suggest they put more of their collection online. http://sounds.bl.uk/information/Public-Collections
You will also find music in the Skiffle section, Jazz Section and Touch Radio section that will play for anyone.
The British Library are at last making sounds available to the general public, beyond charging you to visit them and listen to the recordings.