When your property tax appraisal arrives, you only have a small window to contest it. Be prepared and take pictures of any cracks or anything on your property that might lower your tax value. You can contest in person, but I've found that sending a letter (mailed certified) often prompts them to respond. Also, if you have had recent sales in your area at a lower price for comparable property to yours, send that information too. You should be able to see appraisal values on the appraisal district web site.
Note: If you no longer have an escrow account you may be able to pay half the taxes twice a year instead of at one time. Check with your appraisal district.