Lego technic is a great simple building system quick and you can buy (at a hefty price) the programming system. A cheaper way is go the microprocessor route - You don't say where you are but in most parts of the world you can get Picaxe micro systems. They sell all you need for robotics up to pretty complex concepts. their programming system is free to down load as are their manuals and MUCH information about their kits. their support forum is also particularly good. Start simple - get used to programming - a simple 08Ms and a bought programming PCB (makes life easier at first) a few LEDs and resistors and you are started. Search their forum for starters equipment.