SysLastValue is a kernel-level table that does not show up in the AOT data dictionary. There is however a form called "Usage Data" that can be accessed (check tools / development tools / application objects / usage data). The form itself is called "SysLastValue" (yeah, really) in the AOT. We can use the datasource on the form to right/click and table browse this mysterious table.
SysLastValue stores many different things. The majority of records you will find in there pertain to caching, or "last use" type of data, which will remember the last values you've entered on a dialog, the last printer selection you made for a report, etc. But, which is why we're interested, it will also store any user setup you make on a form, and any and all queries being stored. The field "recordtype" will indicate exactly the type of values stored.
We are interested in type "UserSetup" with the "isKernel" flag set to no, these are the user setups on forms, and the "elementName" field will tell you what form name.
Type "UserSetupQuery" contains the queries saved for a form. You will notice the "designname" contains the form's name, and the "elementname" field contains "f:formname".