Mambots wanted

I dont know if I'm posting in the right section but I need a rating system, a plugin/mambot to make it possible for people to upload their info about their company. Basically what I'm making a review website that uses Joomla software. People will be able to rate certain things and write a review about what they liked and disliked. Also I want it so when they first visit my website they will be prompted with a city list such as the one that craigslist has. I dont know if there is a mambot/plugin for this. Also when they click a certain city they can choose a company within that certain city and they can write a review on that company and rate it. If there are any mambots/plugins for these types of things posting the download links here will surely help me out A LOT!