1) Where do i buy genuine EC5's?

The golden question. Generally large retail stores online that stock for the RC helicopter boys have genuine ones. You can find them on ebay but you need to know what to look for as there are a lot of copies. The main difference being the tolerances involved. Non genuine ones don't stick together as well. Genuine ones go in the back of the plug. Genuine EC8s go in the front though (no idea why but that's the way it is).

2) which are easy to use out of EC8, EC5, Andersons or XT90?

Andersons are easy quite simply because they are so large and don't have tight tolerances on much. EC8s are obviously bigger than EC5s but they are both the same. Haven't used the XT90s so can't comment.

3) What is the standard for ESC, Lipos and Motors in terms of if they are Female or Male, should batteries be Female, should my rage bridge have male for + - and female for motors?

I like to keep my power source side female and load male much in the same way your wall plugs are. So batteries are female. Battery connection on speedo is male. Motor connection on speedos female, motor wiring male. This way you can't accidentally plug a load onto the motor leads of your speedo.