#2
Yes. You can click on your username and then click "Find all posts by ottomated". Another way is to go into your userCP and change the settings so you subscribe to threads you post in then whenever you click UserCP it lists the threads you have posted in that have been updated.
#3
yup, click on 'search' at the top of the page (just under where it says what thread you're in), then under username, type 'ottomated'.

edit: or you could do what the post above me says, that way is easier