Presumably available at any game level.
On playing, you are invited to "Post a message to your friends to raise awareness for Playdom's Help for Haiti campaign. For every friend who participates, we'll make a donation to Partners in Health, and your friends will receive a special in-game item..." The game claimed to have donated $20,000 by 30 January. You may just skip the sharing. Either way, the final message telling how much cash you gained includes a link to Partners in Health at www.pih.org.