I'm trying to setup my business address to take payments via invoice and it will only let me put in an address for America. I'm in the UK though

Make sure you are opening QBO UK version, not US version. Login to your existing account as Primary Admin and navigate to Billing and Subscription menu. If you are paying the subscription not in GBP, it is highly possible you are not using QBO UK version.

https://quickbooks.grsm.io/UK

Hello Sussexpartybales, 

Welcome to the Community page, 

Please can you either ring the support line on 0808 234 5337 line is open mon to fri 8am til 7pm so you can set up a screenshare with the agent on the phone so they can see what your seeing or send us a screenshot here so we can take a look at it more for you.