Many - but not all - records in county records offices in UK can be accessed via the A2A - Access to Archives - website www.a2a.org.uk . It's a good start, but usually you're best contacting your local records office staff about records relating to music, dance, song etc. They're usually very helpful.

Some libraries also have local history sections, which can prove useful in researching local tunes and songs, or the social context of these. My local history librarian has pointed me in the direction of lots of music, tunes, broadside ballads, books with references to songs etc etc. It's a wonderful treasure hunt, and one which I've been on for the past 30 years.

Re. depositing records: I have had trouble with this lately, when looking for a home for a particular collection (which had come my way from a musician and collector who had died some years go). Records offices have little space, fewer staff and less funding these days and I have been sent from one to another trying to find someone willing to house an important local collection. They seemed to be wanting to find reasons to refuse, suggesting Vaughan Williams Memorial Library - who had already said they had no space, no staff to catalogue etc etc ...

We need to be able to deposit material on traditional music, dance and song for future generations, but it seems as though the places to deposit such treasures may well get fewer as their funding gets squeezed.