We booked here: http://www.montenegrohotels.org/eng/hotel.php?hid=38#
It works out at about €50 or €60 each a night for a single room. I know what you mean about the hotels in Podgorica. They all want you to send off an enquiry as opposed to just being able to book over the internet. When they responded to our enquiry they said that the prices for next season weren't available yet so we just asked them to make the booking on the basis that the price would be in and around what it is now. They guaranteed that would be the case and were happy to take the booking on that basis.