Enter the chart data manually just as you would do for a person.
Select Regiomontanus for the house system, Liz Green for the chart style, select Pars Fortuna to be displayed on the chart.
The resulting chart shows applying and separating aspects, but unfortunately doesn't have the option of showing essential dignities, antiscia or other horary consideration.
Nonetheless, I think Astro.com is a good site for generating your horary charts. The best option would be to buy your own astrological software and I'd recommend you Janus (
www.astrology-house.com) it's $149, but a great piece of software, excellent graphics, lots of accurate calculations. It's used by horary masters like John Frawley, Sue Ward or Robert Zoller.
Radu