abducted

hello ! I'm from france, and a long time ago, I found on waveidea.com all the things needed to build a midi controller : the bitstream. Here is a link : http://www.angelfire.com/funky/zeltron1/DIYbitstream.zip Now of course they sell the bitstream pro which is a ready made controller but it is expensive. I'd like to build the old diy bitstream. What do you think ? Would it be expensive ? I think the microchip is quite expensive, and I don't know how to program it... Thanks for your time !