I have been doing some research on directory software for sometime and I have to say this is the best product I have come across. SOBI2 is has loads of features, highly customisable and adaptable to any type of listing and directory needs. Without any prior experience in Joomla and PHP I was able to install and use easily. There is a great support forum as well.
I have been using SOBI2 for some months now and I am very impressed. I can highly recommend it. Best of all, it is FREE!