A local Real Estate agent can run this down for you. You can contact the agent who helped you buy your home or perhaps another agent who responds to your question may be willing to help.
You could search the county records site online, but this may be difficult.
Other than MLS, you can also search for homes sold before March 31, 2009 on the county property tax appraiser's website. These are the same records the Board will be using for comparison. Type in the Google search bar your 'county name' and 'property tax appraiser'. When you find the website, look for the online search tool. Most county property tax appraiser's websites allow you to search by neighborhood name and a specific time period.
p.s. If this answer helps you, a 'thumbs up' is appreciated.
I understand your situation completely. I can certainly run those comps for you for 2009. Please email me directly at Love2listyou@yahoo.com or call me at (909)816-4766 so that I can get the information from you to run these comps for you. I am always here to help.