Sounds like you're well prepared so far. As far as the humidity, you can make a humidifier from the design in the Do It Yourself section of this site (top left corner list). I made one (well, my man made one for me) and it was pretty easy to put together and it works great.
I bought the $10 dollar heating pad @ walmart. I guess, as long as it doesn't have auto-shut off, you can go cheap or as expensive as you want (they run from $10-$30 at walmart). To make space between the pad and the container, you can buy furniture feet (also at walmart).

Welcome to the site! I've learned everything I just relayed to you from the awesome people in this community, so stick around you're bound to pick up a lot of useful, educational, and insightful info. here. Good luck!