Recently i purchased a raspberry pi from Kits and spares. I am giving the link here
1)Select a memory card with 4 GB. Select 8GB or 16GB or 32GB will be good if you plan to do some heavy work on Raspberry Pi. Me selected the following sd card from sandisk. Here is the link
Its a 32GB ,class 10 memory card from SanDisk
2)Select a good powersupply: Raspberry Pi requires a charger with a rating 5V 500ma-1A adapter for normal operation. But if you want to interface more device into Rpi, either select a good charger with 5V,2A or puchase a powered usb hub.
How to install Raspbian on sdcard from Ubuntu Linux
2)Install image write tool from Ubuntu software center
3)Take image write tool and select the image file of raspbian and select device in which memory card is inserted.
4)After writing image , plug into Rpi memory card holder. Use RCA connector ,or HDMI or plug some HDMI to VGA convertor for the display
5)Do some initial configuration and you will directed to a terminal. Enter "startx" command for getting desktop.. Enjoy