Where do I start with the Star Wars Expanded Universe?

I am a big fan of the Star Wars trilogies. I recently saw a countdown of the top 100 Star Wars characters on IGN. I knew pretty much just the characters from the movies. I'm feeling a little motivated now, and I would really like to dive into the Expanded Universe. The only problem is that there is SOOO much. I don't even know where to start. I very much am a completist, so this is something that has actually bothered me for a while. If anyone can help out, it would be very much appreciated!