Try under a rock, behind a tree, the neighbour, etc, etc... So many possibilities.
Or simply learn the basics of C#(as that's what most of the cruise insim app. developers use), and download one of the free source (cruise) insim/outsim/whateversim bases. Or just look for threads with the name "Can someone code me an insim" or "Where can I find an insim coder", etc... I'm sure there is one of those on the next page in this section. Or maybe even on this one.
Some of those are not cruise insim apps, but just bases. Anyway, they are useful if you want to make something different some day. Or if you want to make a cruise app with nothing but your own code(not counting the base you're using of course ;p).