rebuild MBR wiped out by Windows

Easiest way is as follows , get a copy of system rescue cd 

  http://www.sysresccd.org/SystemRescueCd_Homepage

then boot from CD/DVD drive using system rescue CD , then you will get the option for BOOT AN EXISTING LINUX PARTITION ,choose it. after you have booted into linux go to package manager and search for grub or grub2 depending on your distro and then simply re-install it

BOSS LINUX

ICFOSS

ubuntu in smart phones