How to get started with Mindstorms?
The most current Mindstorms set would be the NXT 2.0. 

 

The set is advertised for children aged 10+ (previously 16+). If you or your child is under 10 but has a talent for building with LEGO and a basic understanding of computers or engineering the whole process should be fairly easy to get to grips with. 

The set itself is quite an investment (RRP £235/$350) yet it provides the most complete Mindstorms package. Half of the time spent playing with the set will probably involve programming via the NXT-G software which comes with the set.




  NXT-G is an intuitive, icon-based drag-and-drop programming language
  designed for an easy introduction to programming for new users and
  experienced users. By choosing program blocks that work with the
  motors and make the sensors react to inputs, you simply build up your
  program block by block, and you can create programs that range from
  simple to complex.
  (Source)