why not go to the websites of big gaming comps to get an idea.
if your thinking of starting one then unless you have money to pay the programmers and artists and music and sound effects makers 3 years worth of wages while they work on making a game that could ( could) be a blockbuster then i wouldnt even condider it.
i noticed on this forum everyone is obsessed with becoming a "company",ive owned 3 businesses and starting them can be hard work,becuase your the boss means somtimes ( a lot actually) you have no money but need to pay the workers no matter what.
try to join a company,then if what you design is a big hit then go solo selling your work.
yearly earnings take years of hard work and commitment b4 you actaully start to see what can be classed as a profit.if you pay out wages every month to workers and you do that for a year then their are no actual profits for a long time.
taking all that into cosideration who knows,you might suddenly stumble onto somthing and make it big overnight.......but i dought it.
the programmer formarly known as thicko.