How do I find a G/L account used before for a specific vendor? Thanks

Welcome to the Community, @julie109.

I can help you search the account in QuickBooks Desktop.

You can also run the General Ledger report to view the vendor transactions associated with the accounts. It provides a column for the vendor names, which you can filter by customizing the report.

Here's how:

1. Click the Reports tab at the top menu bar.
2. Hover the cursor to Accountant & Taxes.
3. Select General Ledger. 
4. Choose the date range.
5. Press Customize Report.
6. Make necessary changes from the Display and Filters tab.
7. Hit OK. 

Additionally, I recommend the following resource, which contains information about how reports work, as well as some tips in customizing them:

• Understand reports
• Customize reports in QuickBooks Desktop

Let me know in the comment section below if you have any other questions. Have a great day ahead.