There's a couple things to take into consideration. Do you want to host the software yourself? If not, look into ticketing solutions like EventBrite or similar. If you're willing to host it, there's a ton of really good solutions available as plugins for WordPress. I work for Modern Tribe, and ...
I've used a ton of different plugins and services to create and sell online courses, and here's the best combination I've found: WordPress + Gumroad + ProductPress 1. WordPress: You'll use WordPress to host your course content. I typically put each lesson in a new Page. 2. Gumroad: Use Gumroad ...
Tip: You'll only do this if you're a Thrillseeker looking to loose massive revenue. You'll never, ever, ever turn over design of any business critical system to anyone in the class of "junior anything" who requires "SQL courses". You'll have an experienced designer handle your SQL design.
What are you looking to do? I am a fan of MeetFox for scheduling and billing for 1:1 coaching sessions. www.shaunnestor.com/recommends/meetfox For training software, there are a million options depending on what you need. I am playing with Wishlist Member right now. Teachable is a decent optio...