When I was in corporate marketing, I was part of Toastmasters. Then, when I started my own business 15 years ago, I joined NSA and went through their speaking program as well as Patricia Fripp's speaking course in Las Vegas. It's been 10 years since I've practiced my craft and after bombing a keynote (you always will have at least one), I realized I lost my mojo. I decided to explore Toastmasters again and finding this particular club in Encinitas has brought my faith back in myself. Although I don't do a lot of keynotes now, I do a lot of podcasts and interviews where I need to be clear and succinct. Toastmasters...especially Table Topics...helps me hone my message on color. If you're interested in learning more about how color can communicate your message, visit justbehue.com for some free resources.
For new members, I'd say start volunteering and helping out. You'll soon get comfortable enough to practice your craft because you'll realize you're among the nicest, most supportive group of professionals in the area. Encinitas Toastmasters are truly the gold standard.