i live in NE ft. worth. medstar is a good place to work, they run their assess off but you get alot of good experience, also the hospitals hire EMTs, pay about 10-11 an hour.
as far as tarrant county, the choices are limited, as medstar has an exclusive contract with 90% of the area here, and the rest is covered my FDs. dallas has alot of options, TLC, lifeguard, dallas ambulance, and a TON others (including the company i work for, we alot of nifty stand-bys).
if you get your I and are NR, you can work for AMR arlington, they are a good system. i dunno about I's, but i know they have a pretty hefty sign on bonus for medics.