The idea of broadcasting your audio files on the internet or 'Podcasting' is very popular in schools at the moment.
This website is also a very useful resource with general information about Podcasting. https://metapress.com/how-to-start-a-podcast/
With Audacity software you can record and edit sounds and import and export WAV, and MP3 files. You can easily edit your sounds using cut, copy, and paste features, mix tracks, or apply effects to your recordings. Here is the link to the free download of the Audacity software.
There are many royalty free music websites here are some below to explore. http://www.seabreezecomputers.com/tips/freemusic.htm
Other useful websites
Sound Cloud is an online audio distribution platform that allows users to upload, record, promote and share their originally-created sounds.
The Audioboo website allows you to easily record and upload short sound files free.
The Podomatic website also allows you to record and create sound files free as well upload any MP3 files you have created.
'Insert' -'Sound from file' or 'Record sound'.