Hubbard City Lakes Park is one of the few national dark night skies in Texas. Typical naked-eye magnitude on a clear moonless night is 6.5. This park is only 1.5 hours from Dallas and 2 hours from Austin and has campsites available ($10/tent - $15/ RV).
Hubbard City Lakes Park is located about two miles south of the town center of Hubbard off of Highway 31. If you're heading south on 31 you'll make a right on to Country Road 3360 (and if you're heading north you'll make a left). It will be a dirt road, but I took my VW wagon on it so most cars should be fine. The further along you get you'll encounter a couple dips, so heads up!
As soon as you make the turn there will be a small playground on your left and if you keep going there will be a little dock that leads into City Lake 3. I took a lot of my photographs on or near the dock. This side of the lake will be the best spot for photographs because the night sky is clearer to the south. But fair warning - if it's a humid night there will be lots of bugs flying around if you have a light on, so bring some bug spray!!
If tramping around without any sort of guidance isn't your thing, there are monthly group tours with the Central Texas Astronomical Society (You can see dates and sign up here). At these events, CTAS members will bring binoculars and telescopes to use! So whether you want to explore on your own or join a guided event, this is an awesome Texas spot to view the night sky!