Please note that you also meet with these people on Omegle and Chatroulette
Java Chat
Java Chat is one of the most preferred chat type on the country. You can talk to people on these rooms easily. You can generally send private messages to anyone on the site but there are also sites where you can only chat on main chat board. Java is not good enough to make you pleased. There are not many features on Java chat sites.
Flash Chat
Flash chat is easiest way to talk to people on the site and there are many flash based chat sites on this country. You can try this chat site to talk people on a flash chat room: http://www.worldchatonline.com/pakistan-chat/karachi-chat-room/ It's a DalNet service and it's free at all. You can meet there people from Karachi. You can find more if you search sites on Google.
IRC
IRC is the oldest way to talk with people. You should download a client for talking to people on this chat type. You can download it from http://www.mirc.com/ It's free
Pakistani people generally know more than one language. They know Urdu, English, Punjabi, Pashto, Sindhi, Saraiki, Balochi, Kashmiri, Brahui, Dogri, Hindko, Shina, Balti, Khowar, Burushaski Yidgha, Dameli, Kalasha, Gawar-Bati, Domaak languages.