I would like opinions from providers on a reasonable amount of time to cancel. Recently I set up an appointment with a provider that contacted me to let me know she would be in my area. I  set the appointment on a Monday for a Wednesday the following week, and then needed to cancel a week in advance. No deposit was required, but I would like to know if I should offer her something for canceling.

I think you are saying you booked 9 days in advance, and cancelled two days later, which was a full week before your scheduled date? Just making sure.
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I dont think I have ever seen a provider have a cancellation policy that extended out 7 days before the meet up, so then it would essentially be up to you as to what to give...or not. Most of the ones I see, when they have a cancelation policy, it is something on the order of:
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Less than 24 hours...100% due
24+ to 48.....50%
49+ to 72.....25%
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So by implication at least, if you cancel before 72 hours, you would owe nothing,  
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That said, I still think it would be nice, and good Karma, if you offered something up as a token and appreciation for her valuable time. Maybe like a $50 or $100 gift card or Venmo? But I am interested in the providers take here as well.

With  regards  to  "Cancellations";
Some  cancel  with  24-48 hour  notice,
occasionally,  the day-of,  if  it's  a  dire
emergency.

7 days is plenty of notice. But should you give her something? I would say it depends how much of her time you took. If you’re a returning client and it took less than 5 minutes, nope. If you’re a new client and she took the time to answer emails and screen you, but it was quick and smooth. Maybe something small. But if you had more questions, back and forth, special requests, etc…, bump it up. It boils down to how much wasted time did you cause.

If you want to see her again I would, especially if you didn’t give a deposit and have never met her before. If one of my regulars is sick or has something going on, I’m generally pretty understanding and I don’t require a cancellation fee. However, when I’m touring, I’ve placed that appointment aside just for you and it’s very likely that someone else has asked for that appointment and I’ve turned them down. If I would at least offer something as she likely will lose money from the cancellation. It’s not necessary but she will certainly appreciate it and want to see you again.

I agree with this take. If the appointment was only on the books for a couple of days and the tour was already planned, she likely hasn’t lost income.

I had a last minute cancel, called the provider to reschedule.  She refused.  I offered to send her some money for the inconvenience.  She just blocked me.  Felt bad, but I did try.  

The most important point on this topic is whether or not the customer is canceling with sufficient advance notice for the provider to book someone else into that time slot.  Based on my experience, 2 to 3 day notice should be sufficient unless it is more than a two hour booking.  If it's an overnight or weekend, then it would be courteous to increase the notice of cancellation, if possible, or in the alternative, pay a partial fee.  

This is a business transaction.  
A one week notice is more than sufficient to cancel without penalty or fear of being ghosted in the future.  
You weren't offering a FMTY date, she contacted you to let you know she would be in town.  

Yeah you offer to keep giving her more business.

I would send her a token of appreciation even if she does not require a deposit, or have a cancellation policy because it's the right thing to do & you stand out from the rest if you want to see her in the future. She knows you value her time.

A token of appreciation always makes someone remembers someone !

Thanks for the input on this I didn't want to come off as trying to waste her time and thought that I gave her sufficient time to rebook the time slot so hopefully she was able to do so, just found it odd that she never replied