If you are willing to do a little investigation on your own, you can compare Tax Assessed Value to Recently Sold Properties. You find Tax Assessed Values at the County Tax Appraiser's office.
As an example you can see a 1 acre property is assessed at $10,000 and sold last week for $20,000. A second 1-acre lot was assessed at $10,000 and sold for $25,000. You can then do some basic math and get in the ball park of determing a sell price by using the assessed value of your land with the expected sale price. If your 1-acre lot appraised for $15,000 then you could set an asking price between 2x to 2.5x the TAV and probably be in the ball park.
I hope this helps.
Sep 9, 2010