I saw 2-3 Merlins and two White-tailed Hawks in Anahuac National Wildlife Refuge
http://www.fws.gov/Refuges/profiles/index.cfm?id=21521
Several Harris's Hawks can be found close to Galveston off Rt. 6 in Hitchcock, Texas. Take Flamingo Isles Blvd. After you cross the bridge, check out the trees on the right hand side over the swampy area.