I use a combination of sources.
Ambleside Online
Excellence in Literature
Personal experience
James Stobaugh literature series: American, British, and World.
Well Trained Mind’s Susan Bauer’s classical list
My son just wants me to assign. He reads sci-fy on his own, but all else, he’s content with being told what to read.
This year, he’s taking a separate writing course online for fall semester and we’re doing WttW together in spring.
I will be reading the same books as he; we’ll discuss and fill out a story chart, ala Teaching the Classics style. The exception being our Shakespeare choices and C.S. Lewis; I have other srudy guides for those. Additionally, my son will be using Stobaugh’s British literature student book for most of his reading, just no essays for me.