Try Skymates on GKY
I just stopped in to Skymates on Arlington airport today. They have a Piper Seneca for $170/hr and $155/ 10 hr block. I have been looking around the area and the prices have gone up considerably in the past year. From what I've heard the insurance costs have gone up quite a bit.
Please, STAY AWAY FROM INTERNATIONAL AVIATION AND TRAVEL ACADEMY. IATA has caused many people alot of problems. I could go on for hours about that school. They are using skymates aircraft and charging more than Skymates.
There are also a couple of schools up in Denton that are good from what I've been told. The one that I have heard of was charging 148/hr for a Seneca. Try to PM flyby, he instructs up there.
I haven't flown with either Skymates or the schools in Denton, so you may want to see if anyone else has. I guess it depends on what part of the metroplex your in and where you want to fly. I have flown out of GKY and 52F most of the time, but I am definately more familiar with the central and western part.
Good Luck
Brokepilot