Just because the House of Representatives has voted to defund the Affordable Care Act doesn't mean Obamacare has been defunded. The spending bill passed by the Republican-controlled House on Friday isn't yet a law.
Before the bill can become law, it will have to be passed by the Senate and then signed by President Obama. It's extremely unlikely that the Democratic-controlled Senate will pass the bill. Even if it does, President Obama will veto it.
No matter how you feel about the ACA, don't be misled by political wrangling; the ACA is still the law. You'll still be able to enroll in Obamacare starting October 1, 2013. You'll still be subject to a tax penalty if you're uninsured in 2014.