To search through the list of tables in the DB:
Dim tdf as TableDef
Dim MatchingTable as String
For each tdf in CurrentDB.TableDefs
If tdf.Name Like Cat & "*" Then
MatchingTable = tdf.Name
Exit For
End If
Next
If MatchingTable = "" Then 'table not found
Msgbox...
End If
To then search the table:
'Dlookup returns a null value if nothing found
str = Nz(Dlookup("<Name of field>",MatchingTable,"AssetNumber = " & AssetNum),"")
If str = "" Then 'asset num not found
Msgbox...
End If