Click your name over your avatar, and then choose "find all posts by lmills730" from the little drop menu that appears
That will show you all of your posts.
You can also auto-subscribe to any threads you create or post in. Go to your UserCP, choose "edit options", then look for the message subscription options. You can choose to subscribe to every post automatically. You can get an email every time someone replies if you wish. You will also be able to find those posts in your UserCP under 'subscribed threads'