mine is just a big old rubbermaid water trough.
we've use an old rubbermaid tote.
i've seen one that was just a 2x4 frame, one end with thin particle board for sides and end cap, the other covered in chicken wire, with a hinged top.
basically, you can use anything that will contain your birds.
when it was hot and my chicks didn't have feathers, yet, i just a 100@ household bulb in my lamp. otherwise, a 250W heat lamp
doesn't have to be anything extravagant, but it can be if you want it to.