You can change ypur pi IP address instantly when you boot your pi up by doing the following:
Type ifconfig and write down your current "Mask:" example it could be 255.255.0.0
sudo ifconfig eth0 192.168.0.xx netmask xx.xx.xx.xx
Where xx is whatever you want yout new ip to be and what your current subnet mask is. Just dont type in an ip thats already being used obviously
Type ifconfig again to verify your ip and submet mask are updated and correct.
DO NOT reboot the pi as this well revert the changes back.
Try loading up a dc browser and goto google.com.
If this works we can setup a static ip in the pi itself for u.