Federal Historic Preservation Tax Incentives Program
The 20% tax credit is available for buildings rehabilitated for commercial, industrial, agricultural or rental residential purposes on projects that are certified historic structures.  The 10% credit is available for rehabilitation of non-historic, non-residential buildings built before 1936. 

Below are links that you may find useful. 
Texas Historical Commission: www.thc.state.tx
American Planning Association: www.apa.org
American Institute of Architects: www.aiaonline.com
Livable Communities Task Force: www.house.gov/blumenauer/livable.htm
National Trust for Historic Preservation: www.nthp.org
Texas Downtown Association: www.texasdowntown.org
Sacred Places: www.sacredplaces.org
Scenic America: www.scenic.org
American Society of Landscape Architects: www.asla.org
Institute for Cultural Landscape Studies: www.icls.harvard.edu
The Cultural Landscape Foundation: www.tclf.org
The Alliance for Historic Landscape Preservation: www.ahlp.org
The Handbook of Texas Online: www.tsha.utexas.edu/handbook/online
Texas Parks and Wildlife: www.tpwd.state.tx.us
Texas State Preservation Board: www.tspb.state.tx.us
Advisory Council on Historic Preservation: www.achp.gov
Preservation Directory: www.preservationdirectory.com
The Alliance for National Heritage Areas: www.cofc.edu/~heritage
Office of Rural Community Affairs: www.orca.state.tx.us
Rails to Trails: www.railstotrails.org
Texas Rural Leadership Program: www.trlp.org

For more information, contact Cheryl Green at 903-464-4440.