Hello there, @david-seber.

As mention by my colleague above, typing an initial letter isn't an issue in the system. You'll need to select the drop-down arrow to enter the name of your vendor/ customer.

Know that you can always visit our Help Articles page for QuickBooks Desktop in case you need some tips and related articles for your future tasks.

If there's anything else that I can help you with, please let me know in the comment section down below. I'll be always around ready to help.