I want to make mash ups, but I don’t know how to.
Can you tell me how I would go about editing audio and putting tracks together with free software?
Also,see the below article which has accompanying video to help you -
How to Make a Mashup With Audacity
If you need royalty free music :
Make a Mashup in Audacity
There is quite an indepth write-up on how to create a mash-up with a link to the software required here: