You can correct other people's notebooks and as well write your own sentences that will be corrected by native speakers. You can come up with interesting topic for conversation in a language that you want to learn. You can ask grammatical questions. You can talk with native speakers and listen to their specific pronunciation and so onand so on....

Good luck.

Under notebook posts, you could choose to record or type and respond by recording or typing back.  I haven't tried  recording any responses but, i do see the icon on the bottom of a correction post.

If I were in your shoes, i would type Edward.Watson81 and talk with Edward

My suggestion would be to simply DO SOMETHING everyday. Like you have already mentioned, there so many natove speakers out there to help you out! I just started using italki as well and since I am on a tight budget (college student) I am still not able to book a session/ course with any intructure. As for now, I am trying to write sth in the language that I am learning everyday! Like one notebook post for each language and I am trying to become a community tutor. When my next paycheck arrives, I will definitely book a class!

Whatever you try on here, I recommend that you are patient. With some people, you will speak regularly and with others you will not. With some you will have more of a cultural exchange than language exchange. I would say to be open to learning whatever you can.