I just highlighted the value of joining real conferences. Besides getting to know more about the topics, it is alway a great opportunity to get in touch with people and grow your network. But sometimes the pricetag can be high or the location is really out of the way. So another good source for joining a conference (in a less interactive manner, not sitting there), is to watch the video transcripts that you find occasionally online. Be aware, there a lots and lots of them and you might spend the whole day watching that stuff.
Todays recommendation: 10 Ways to Screw Up with Scrum and XP by Henrik Kniberg (Agile Conference 2008, Toronto, link)