Click Settings at the top right
Click General Settings in the lefthand menu bar
Scroll down to Messaging and Notification
"Default Thread Subscription Mode", brings a drop menu where you can choose how you would like to be alerted
Scroll to the bottom of the page & click save changes on the right.
No problem I prefer using the "From my Control Panel" option as opposed to emails. You may end up with loads of emails where you don't need to even leave BL to check by just clicking settings at the top of the site and seeing if there are any threads listed. For example, if there weren't any threads showing up, then no one has responded. If there is a thread there, then it means people have posted since you've posted in the thread. All personal preferences though.