Been done quite a lot here's an easy and more up to date tutorial from Rasathus' Raspberry Ramblings - @Rasathus
http://rasathus.blog...p-easy-way.html
To build your own Raspberry Pi laptop, you'll need the following items ...
1 x Raspberry Pi Revision 2
1 x Motorola Atrix LapDock (UK , US)
1 x Female USB Micro to Male USB A connector (UK , US)
1 x Micro USB Female to Male extension cable (UK , US)
1 x Female Micro HDMI to HDMI Male connector (UK , US)
1 x HDMI coupler (UK , US)
1 x 30cm HDMI cable (UK , US)
NOTE: LAPDOCK 100 AND RASPBERRYPI aren't as friendly as the older model. HDMI output on the 100 is touchy. But the old model works quite well.