i've just breezed through some of the major biblical arguments on gambling and the only one that i saw that held some reasonable water was the idea that it is a greedy/covetous practice to gamble for money when you could just as easily gamble for no money for fun.
this is not necessarily true. you can't gamble for fun in vegas. if you're a responsible person and fully recognize the fact that you're going to come out of the experience with less money than you started with, i don't see how its covetous or greedy. as long as you have a budget and spend no more than you're willing to lose and gambling smart to try and maximise your personal enjoyment, not taking the risk for the possible return, i personally don't see much harm.
as for the fornication thing, yes the bible says something to that effect. googled <a href="http://www.libchrist.com/bible/fornication.html" target="_blank">this</a> and it might be worth your read.