The DLS has some great ones:
<kuid2:373500:100024:8> FDL Fond du Lac for T:ANE has several sessions
<kuid:44878:102181> a dg uintah rwy 2019- june 2022 has some sessions made by pitkin. Great for desert scenery!
If you are into model railroads, Philskene has a bunch of great ones, and there are always multiple sessions available:
<kuid2:69871:3589:1> TRS19 - The Deepwater Railroad Co - Model Trainz Layout
<kuid2:69871:3671:2> TRS19 - The Hoofhearted & Smelz RRCo - NG24 Model Trainz Layout
<kuid2:69871:3536:1> TRS19 - The Hoofhearted & Smelz RRCo - NG Model Trainz Layout
<kuid2:69871:3625:1> TRS19 - The Jenn Erik Railroad - a generic NG36 Model Trainz Layout
<kuid2:69871:3602:1> TRS19 - The IntenCity Railroad - Model Trainz Layout
<kuid2:69871:3516:1> TRS19 - The Klozett RRCo - NG Model Trainz Layout
<kuid2:69871:3595:1> TRS19 - The Krashnburne Railroad - Model Trainz Layout
<kuid2:69871:3541:1> TRS19 - The Lilliput Logger - SG Model Trainz Layout
<kuid2:69871:3498:1> TRS19 - The Mann, Phrom, Laramee RR - Model Trainz Layout
<kuid2:69871:3503:3> TRS19 - The Phootnote & Fourword Railroad - Model Trainz Layout
<kuid2:69871:3609:2> TRS19 - The Port Loleta Railroad Co - Model Trainz Layout
<kuid2:69871:3534:2> TRS19 - The Port Zyd & Fulazturn Railroad - Model Trainz Update 2
<kuid2:69871:3577:2> TRS19 - The Rivercide Electric Railroad Co
<kuid2:69871:3583:2> TRS19 - The Rivercide Railroad Co
<kuid2:69871:3539:1> TRS19 - The Yuan Gulch RRCo - NG Trainz Model Layout
And if you like to try Down Under, there are sessions available for these:
<kuid2:56603:100171:1> WeddinNSW V5.1: Blayney-Galong-Cootamundra
<kuid2:56603:100832:2> WeddinNSW: South lines to the Lachlan
Or France, there is <kuid:458053:104131> SGLM with sessions
Back in the US, there is <kuid:425968:100010> BNSF: Clovis to Lubbock
Enjoy!!