How can I look up a check written by the person's name?

Hi you can check it through the Gear icon, tracycarlsonhall.

Let me show you how search the user's name who made the check. 

1. In your QuickBooks Online (QBO) company.
2. Go to the Gear icon and select Audit Log.
3. Click on the Filter buton, and seach for the user.
4. Tick the box for the Transactions and select Apply. 

Now you can see the the list of transactions made in QBO as well as the users who made it.

You can check this article for more information in using the audit log in QuickBooks Online.

Loop me in if you need further assistance. I'm here to help you. Take care.