1. Laptop Screen: You will need a controller board:
The seller's name is 'njytouch':http://www.ebay.com/sch/njytouch/m.html ... =12&_rdc=1
Check some of his posting and they have listings of all supported screens. If you do not see your screen's model number contact them and they can check it.
Google Xbox 360 VGA Mod to see the pins you need to solder.
There is guy called 'darkuncle33' here and on youtube. He does great slim Xbox 360 laptops. Contact him for tips. Also watch some of Ben Heck's videos on how to create Xbox 360 laptop.
2. Adding Keyboard:
You can probably solder usb cable from keyboard to Xbox 360 motherboard. You have to find out the pins for USB.
3. Storage Device:
The drive has SATA connector so you should be able to get some kind of extension cable for SATA so you can place the harddrive anywhere in your case.
Engadet ran a whole article on how to create your own Xbox 360 laptop. It is UP to you on how complicated you want it to be.