I found Toastmasters to be fairly reliable for practicing and improving my public speaking skills.

In my city, there are dozens of chapters that vary in quality and expertise. One chapter is really good for people who are shy. Another is for people who are quite advanced and are trying to get on the level of event speaker.

Over a few years, my speech writing and delivery improved to the point where I got compliments during public events. And a friend of mine from the club got to the point where he frequently gets asked to be an MC at friends/family events.

Plus generally speaking, I have found the people who go to be friendly.