Here are some links to other related sites:
Instrument Forums are dedicated to helping learners and players learn and improve by providing access to tunes, advice on instrument playing, access to other musicians, and tips on instrument repair. These are the main ones I follow and contribute to:
LEARNING TUNES: Here are some sites that offer you access to a large range of tunes. A great place to get started and often a source of information on what and where to buy music etc:
www.comhaltas.ie for all things Irish music
https://dartingtonmorrismen.org.uk/tunes great source of Morris tunes
www.thesession.org for info on tunes and session venues etc
BUYING & SELLING MUSICAL INSTRUMENTS: I use these site regularly when buying and selling instruments:
Paypal: www.paypal.com
Probably the easiest way to make an online payment to another person. I use this for most of my musical instrument, buy and sell, transactions.
Xe Currency Converter: https://www.xe.com/currencyconverter/
I use this tool to calculate the cost of an instrument, in my currency, that I may be thinking of buying from another country.