Lattice FPGA development board

Hi,

I am a beginner who recently become interested in learning some 
knowledge and skills in FPGA development. My friend recommends me a 
Lattice FPGA camera development kit as he says it is affordable.

http://www.latticesemi.com/hdr60

But I know nothing about FPGA and its programming language. I am 
wondering if somebody could kindly answer my following questions:

1) In addition to the kit, do I also need to purchase software from 
Lattice? Is there any free software to use for FPGA development?
2) What programming language should I use for this kit, HDL or Verilog?
3) Is there anything else I need to prepare for this kit?

Thanks for your time,

Eric