These items are found via a new tab in the game's marketplace. There is a new crop called Habitat Peppers that costs 8 City Cash per plot but offers instant growth and 760 Goods per square, or you can also purchase a "Habitat Supplies" shipping liner that will return after just five minutes with 1,665 Goods. Each Habitat Supplies ship costs 15 City Cash.
The big item here though is the Habitat Community, a new home that offers 3,500 - 6,500 citizens to your town, and 40 coins in rent every five minutes. It costs $10 to purchase, but again, all proceeds go directly to charity, and not Zynga's proverbial pockets. There doesn't seem to be an in-game time limit for how long you have to purchase items to help charity, but I wouldn't personally expect these items to stick around for much longer after the new year. If you need any extra incentive, just think of the exclusivity of this Habitat Community - you'll have an item that you can show off to your friends for weeks and months to come, and you'll know that you helped others in need in the process. That's pretty good, right?
Will you purchase any of these items to help Habitat for Humanity via CityVille? Which one(s)? Sound off in the comments.