Greyhound travels between Dallas and Austin Texas. I would think there would be local transportation from the Greyhound Terminal to Fort Worth Airport available as well. You would have to ask at the station.
205 miles
215 miles
About 210 miles
Austin
If using airports as a reference, Austin Airport is 212 miles from Dallas Love Field. Houston Airport is 255 miles from Dallas Love Field. Therefore, Austin is closer to Dallas.
To get from Dallas, TX to Amarillo, TX, you can take I-35W N to I-35 N, then follow I-35 N to US-287 N in Sheppard. Continue on US-287 N to Amarillo. The total drive is roughly 4 hours and 30 minutes, depending on traffic and weather conditions.
Waco is about halfway between Dallas and Austin. You can make any of the following: Dallas Love Field (DAL), Dallas-Fort Worth International Airport (DFW), or Austin-Bergstrom International Airport (AUS)
Houston is closer to Austin than it is to Dallas. The driving distance to Austin is 165 miles per Map Quest. The driving distance to Dallas is 238 miles per Map Quest.
The nearest major airport is Dallas/Fort Worth International Airport (DFW / KDFW). This airport has international and domestic flights from Dallas, Texas and is about 27 driving miles from the center of Denton.
192 Miles
215 miles
Dallas Love Field (DAL / KDAL). This airport has domestic flights from Dallas and is about 22 driving miles from the center of Desoto.