Cartes du Ciel is free software released under the terms of the
GNU General Public License
Shows the position, magnitude, Sun elongation, phase, rise, culmination and set time for the selected asteroid.
You can simply select an asteroid from a picklist by clicking the combobox. This way, you can only select from the first 500 asteroids. The good part is that you can search for any listed asteroid, simply enter (a part of) the name or number, press the filter button, and select the asteroid from the combobox.
Before you can show or search for asteroids, you must have previously downloaded a file with the orbital elements of asteroids. To learn about that, read this.