I went to 3 different places, B&Q was one of them but the other 2 where kitchen designers and fitters. I got them all to design me a kitchen on their software, I just took the dimensions with doors,windows etc and they used their stuff to design the kitchen and printed it out for me. I now have 3 designs but I am not getting them to supply or fit the kitchen, I am getting a different builder to do it for me.
Its a free and easy way of getting it done, I did try lots of different software but I didnt get the hang of them.
btw....some dedicated kitchen places have design software on their websites, B&Q have one too.