There are a bunch of changes, especially with most of DPS going digital. Your best bet for info is to list the counties/cities/towns along your route, then consult the Database (link at the top of this page) and put in what you may need.
Waco is using a Motorola TRS. McLennan County is on the TRS, but it still uses its conventional system, since it does dispatch for several of the smaller towns.
There are several conventional analog and trunked, both analog and digital, systems along your route. Just about all the different trunked systems can be found between TXKA and Waco. Most are easy to figure out, but I just hope you can figure out Ft. Worth, and be able to wade through the potpourri in the Dallas area.
;^>
You will primarily be in VHF land, which means a lot of programming, but there are a few UHF systems along the way (Dallas, for example).
And, there are a few of what I call the paranoid systems, MA/Comm ProVoice with encrypted control channel around too.
:^p
Looks like some specifics were answered by hiegtx while I was typing.
Grazie tanto.