Hello @ericet,
Thank You for posting your query onto the Forum.
When it comes to using icons in the Power BI reports page mostly we all prefer to use the icons from the “Flaticons” website. So below the link of that website provided for the reference from where you can download the free icons as well as premium one’s as well.
Also you can participate into the Power BI Data Challenges as well and where the winner of the challenge can also get the subscription to preimum version of the flaticons. @BrianJ has created a post for that. Below is the link provided for the reference of that post as well.
Hoping you find this useful and meets your requirements that you’ve been looking for. 
Thanks and Warm Regards,
Harsh