www.sina.com www.sohu.com www.people.com.cn These websites are usually used by me.So I think it maybe useful for you.

I think this is a good website:www.cctv.com,it will makes you konw more about China.

it's not a social networking site but it is good for improving your chinese. you could try http://imandarinpod.com. they upload two lessons a week. the lessons not only help your chinese but you can learn about chinese culture. oh and it's free too haha. it also has a special chinese news section. where an announcer reads the news in a slower speed and you can follow along with the pdf

http://www.xinhuanet.com/ this is so called 新华网, you can get all the news happended in china.but it is to long and to large even for me to read all of it`s news. so i suggese you ask your friends to tell you what happends in china today

Download QQ , QQ is a very popular Chatting tool in China , all most Chinese people have QQ . tell me your E-mail , I will send you QQ software of English !