On-demand prices from amazons pricing page https://aws.amazon.com/ec2/pricing/on-demand/ (select Virginia region):

p3.2xlarge: 8 vCPU, 61 GB RAM, $3.06/h

p3.8xlarge: 32 vCPU, 244 GB, $12.24/h

p3.16xlarge: 64v CPU, 488 GB., $24.48/h

Unfortunately, P3 isn't listed yet, but this is my go to site for EC2 pricing: http://www.ec2instances.info/

Oh, it is now listed. Be sure to click on "Columns" and add "GPU" to see the different options

showing up for me on https://aws.amazon.com/ec2/pricing/ for each of On-Demand Instances, Reserved Instances, Spot Instances, and Dedicated Hosts pricing lists. Are you selecting the regions where this is available - US East (N. Virginia), US West (Oregon), EU West (Ireland) and Asia Pacific (Tokyo)?

This got me. Seems they aren't yet available in the Ohio region.