Hi there,
I am not aware of any online training in performance testing. I can very much recommend 'The every computer performance book' by Bob Wescott. All the essentials are in the book, written down in a non-technical way. I have new performance testers in my company read this book first.
Regarding tools, JMeter is used a lot as a free tool, it has a bit of a learning curve. I think JMeter is better if you already understand the basics of perfromance testing. I have great experience with Neoload. Very intuitive, very powerfull in variable correlation. You can register for a free license up till 50 concurrent users. More than enough to do some basic testing. The great thing is if you can show what you can do with such a tool you get commitment for licences easier.
Good luck, Robert Bos