Funny you should ask. I have been working on the Texas Railroad page in the database, accessed by going to the Texas page and clicking on Railroads. I know BNSF and Union Pacific both have subdivisions through the area, via Sweetwater and Fort Worth. I am working on getting all the information, as I am not much of a railfan, but we didn't have a wealth of information on our database, so myself and KD5DGA have been working on it. For now, try:
160.425 - BNSF Telephone PBX Repeater Sweetwater
160.935 - BNSF Lampasas Subdivision (Sweetwater to Temple)
160.410 - UP Baird Subdivision (Sweetwater to Fort Worth)
There is an old line that used to run north out of Abilene, still shows up on road maps, but there are no railroad frequencies in the counties north of Abilene. Best guess is the old Abilene and Northern Railroad that was merged with Missouri Pacific in the 70's.
If and when I discover some more railroad frequencies in the area, I will post them here. In the meanwhile, you could search the railroad frequencies: 160.215 to 161.565. See if anything else jumps out at you.