First, to be eligible, you must have used the home sold or being sold as a principle residence consecutively for 5 of the last 8 years. Second, your income limits are $125,000 if filing single and $225,000 if married filing jointly. Third, the home purchased must be less than $800,000. Fourth, a written contract to purchase must be in effect on April 30th, 2010 and must close by July 1, 2010. Lastly, if you meet the above criteria, then you would receive a $6500 tax credit ($3250 if married filing seperately). So as you can see there are no provisions for refinancing your home. Hope this helps.
If you have any further questions you may contact me via email at firstname.lastname@example.org as I am right here in Wichita, KS.