Ok, so any place near the Vatican is ruled out then...

Options:
Hotel Alpi - near Termini (is this walking distance to Trevi/Spanish steps?)

Hotel Abruzzi - near Pantheon

Hotel Julia

Lalumiere & Barberini don't have openings.

If what you want is to be close to the Spanish Steps, try the Hotel Panda. It is just around the corner...mere feet away, on a quiet little street. It's also low priced (or it was when we were there, Jan. '05). Try its website, www.hotelpanda.it. I would definitely stay there again. There's no breakfast though. We loved the location and found the staff helpful and accommodating.