From About Health:

How Much Is the Health Insurance Penalty for an Individual?

From the article:

Will you have to pay a tax penalty for not having health insurance? How much is the health insurance penalty? Will it be cheaper to go without health insurance and pay the penalty, or to buy health insurance?

http://healthinsurance.about.com/od/reform/a/What-Is-The-Penalty-For-Not-Having-Health-Insurance.htm