In a MOSFET you want to look at the rDS values in the datasheet. These depend on the Vgs voltage used to turn it on or enhance it as well as the temperature.
We don't generally define BJTs in terms of resistance. These need to generally be modeled as diodes. Of course they do have current and power limitations which you need to be aware of. Again this information is available in the datasheets.
For DC output resistance, run a DC simulation, swept through the operation point(s) you need.
For AC output resistance, run an XF simulation, or an AC simulation with a unit current source injecting onto the output.