"astounded about" is a correct and usable phrase in written English.
It is typically used to describe a feeling of surprise or amazement about something. Example: "I was astounded about the news of his sudden promotion. I never expected him to get such a big opportunity."
"I lost control of my bladder," Dugard told Sawyer in one of many moments in the interview where she appeared astounded she was talking about herself.
She thinks that Ashe would have had a Twitter account, that he would have been engaged in dialogue about gay marriage and astounded by the prize money handed out at the United States Open.
I am still astounded and shocked to this day about what was asked of me, and why I had to provide proof, and how they went about speaking to me, with absolutely zero compassion.
"He got out into the boat with them and the wind ceased, and they were utterly astounded, for they did not understand about the loaves but their hearts were hardened". In other words, Jesus had multiplied loaves and fishes in a previous scene.
When I did impress a couple of gym bunnies on Eighth Avenue with my lapidary roll, they simply parked themselves in my path, astounded that they had just read "a whole article" about these gizmos in a men's fashion magazine.
Mr. Myers, he said, "had the airplane off the ground in an incredibly short roll," then made "a steep approach" and finally "landed in about 500 feet, rolled up to our astounded group and let off an ashen-faced flight commander".
The FCC adopted compulsory net neutrality rules in defiance of just about everybody including the courts and an astounded Congress with its jaw agape.
"I'm astounded," said one Trump supporter in Phoenix, upon hearing about Pence's anti-abortion record.
"If we have been wrong, I will be astounded". If today's findings hold in humans, "all theories about the ageing of the female reproductive system will have to be revisited," said Prof Tilly.
