下面这些源更适合于教育网，网易和搜狐的源都可以。
修改/etc/apt/sources.list
sudo apt-get gedit /etc/apt/sources.list
#电子科大的源
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-backports main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-proposed main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-security main restricted universe multiverse
deb http://ubuntu.uestc.edu.cn/ubuntu/ lucid-updates main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-backports main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-proposed main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-security main restricted universe multiverse
deb-src http://ubuntu.uestc.edu.cn/ubuntu/ lucid-updates main restricted universe multiverse
#中科大更新源
deb http://debian.ustc.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb http://debian.ustc.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb http://debian.ustc.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb http://debian.ustc.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb http://debian.ustc.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb-src http://debian.ustc.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
网易的源
deb http://mirrors.163.com/ubuntu/ lucid main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ lucid-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ lucid-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ lucid-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ lucid-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ lucid-backports main restricted universe multiverse
#搜狐的源
deb http://mirrors.sohu.com/ubuntu/ lucid main restricted
deb-src http://mirrors.sohu.com/ubuntu/ lucid main restricted
deb http://mirrors.sohu.com/ubuntu/ lucid-updates main restricted
deb-src http://mirrors.sohu.com/ubuntu/ lucid-updates main restricted
deb http://mirrors.sohu.com/ubuntu/ lucid universe
deb-src http://mirrors.sohu.com/ubuntu/ lucid universe
deb http://mirrors.sohu.com/ubuntu/ lucid-updates universe
deb-src http://mirrors.sohu.com/ubuntu/ lucid-updates universe
deb http://mirrors.sohu.com/ubuntu/ lucid multiverse
deb-src http://mirrors.sohu.com/ubuntu/ lucid multiverse
deb http://mirrors.sohu.com/ubuntu/ lucid-updates multiverse
deb-src http://mirrors.sohu.com/ubuntu/ lucid-updates multiverse
#北交更新源
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-backports main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-proposed main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-security main multiverse restricted universe
deb http://mirror.bjtu.edu.cn/ubuntu/ karmic-updates main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-backports main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-proposed main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-security main multiverse restricted universe
deb-src http://mirror.bjtu.edu.cn/ubuntu/ karmic-updates main multiverse restricted universe
#武汉大学自强网
deb http://mirror.ziqiang.net/ubuntu/ jaunty main restricted universe multiverse
deb http://mirror.ziqiang.net/ubuntu/ jaunty-backports main restricted universe multiverse
deb http://mirror.ziqiang.net/ubuntu/ jaunty-proposed main restricted universe multiverse
deb http://mirror.ziqiang.net/ubuntu/ jaunty-security main restricted universe multiverse
deb http://mirror.ziqiang.net/ubuntu/ jaunty-updates main restricted universe multiverse
deb-src http://mirror.ziqiang.net/ubuntu/ jaunty main restricted universe multiverse
deb-src http://mirror.ziqiang.net/ubuntu/ jaunty-backports main restricted universe multiverse
deb-src http://mirror.ziqiang.net/ubuntu/ jaunty-proposed main restricted universe multiverse
deb-src http://mirror.ziqiang.net/ubuntu/ jaunty-security main restricted universe multiverse
deb-src http://mirror.ziqiang.net/ubuntu/ jaunty-updates main restricted universe multiverse
#上交的源
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
deb http://ftp.sjtu.edu.cn/ubuntu-cn/ lucid main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-backports main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-proposed main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-security main multiverse restricted universe
deb-src http://ftp.sjtu.edu.cn/ubuntu/ lucid-updates main multiverse restricted universe
（原文地址：http://blogold.chinaunix.net/u3/113413/showart_2225679.html）