Hi,
I am also a new WRF user.
From what I understood, tslist output some fields at the nearest grid point. This point is determined at the beginning of the simulation, you have the indices of the points in the first line of the file if I remember well.
You can search in the forum, some questions about tslist have been answered
The output frequency is directly your simulation time step. I don't think you can change that. You may then post-process to get a value every hour.
I am using your topics to mention a small limitation of tslists :
If using a parent and a nest with a vertical nesting (nest having more eta levels than parent), the number of levels output (max_ts_levels) is limited by the parent number of eta levels (e_vert), even in the nest.
Mathieu