Had a visiting provider stand me up last week after she contacted me to set up the date.

Interesting choice of words: she contacted you to set up the date, not other way around? Just asking...

on a big sign and put it on your front lawn where everyone who drives by your house will be sure to notice it.  Bad publicity is the way you get someone's attention for poor customer service.

Were you on her mailing list? Or have you seen her before? If you've seen her before, you can write a review of that encounter and maybe mention the NCNS in the review IF the time you saw her was within three months.

Even if she gives you a reasonable sounding explanation you have to decide if she is telling the truth.  I had a lady give me a story that if true was a 100% acceptable reason for a NCNS.  The only problem is I knew for a fact that it was a big old lie.  Leap of faith!   bigdell

This is true. The key is if the excuse is accompanied by a genuine apology and an offer.

2 sides of every story. Why she didn't show up and why she canceled at last minute?  
Maybe you did something fishy or anything that make her feel uncomfortable about the meeting?

And I didn't report it anywhere. The girl got back to me and offered a plausible excuse. Plus, I don't think it's necessarily a big enough deal to warrant letting everyone know. Stuff happens.  

It happened to me too and to this day the bitch never bothered to explain herself.
I'm still mulling the idea of posting about her on my local board.

and for the record, I have ZERO problem with hookers telling each other which johns/janes are wasting their valuable time by pulling the same kind of crap.

tell the story here, on the GD board, and your local regional board.  I did not name the provider, but told readers they could PM me for her name and I would provide it.  That helps to avoid a shitstorm from the provider.

Am thinking of how to pursue a 'reputable' agency who cancelled when I was on my way to see the provider and when I made the appointment just 3 hours back. Still thinking how best to handle this because the agency was trying to be too smart with me and that I do not appreciate.

So this one is tricky. The provider did not show up yesterday after saying that she was on her way and was stuck in traffic. I waited for more than an hour and kept emailing her as she only communicates through emails. She has a lot of good reviews and all the information checked out. She even asked for a deposit which seemed like a common practice as I have given that before as it a safety net for a no show client and she had a lot of reviews which made me feel confident.  
What is puzzling that she said that she was on her way and didn't show up and hasn't been replying to my emails since

Giving a deposit is NOT standard practice, and now you know why.

So setup an appointment with a highly reviewed provider  9+ rating. Through P411 ... A few emails back and forth... tentative plans to meet at my hotel for an 7 am visit ... I say tenative because she agreed for morning I asked for 7am the day before and then she ghosted ... tried to reach out that morning later that afternoon and a few days later ... nothing... but I see she was active on twitter and p411
It really screrewed up my plans for the week... does this qualify for a public shaming?  I don't know but pisses me off that I was ignored ... just not professional in my opinion

to ever give a deposit. I never understood why guys do that?

Agreed thanks for the advice...

Sorry to hear this happened to you. I would first try to reach out to her through email and asked what happened. Providers are humans just like us and have lives. In my opinion this would be my first step. Outting someone if so go to her regional board for the NCNS if you must.

As someone who's been doing this for less than a year, I can tell you that my first NCNS bothered me a lot since I was nervous to begin with and the NCNS pressure was a lot to take at that time.