+1 for Lynda.com
I have been "using" Illustrator for years now, and I'm also somewhat familiar with CorelDraw too (from way back when I used to use PC for design).
Some recent threads have re-ignited my passion to learn Illustrator, and I am a yearly subscriber of Lynda.com (best investment you'll make), so I decided (two days ago) to go through the entire Illustrator CS5 training (the one-on-one series with Deke McClelland). Great instructor in my opinion. At first, I was picking and choosing topics and I am being blown away by what I'm learning, but now I've decided to start at the basics and work my way through the classes in order!
My end goal is to become proficient at creating vector artwork and thinking outside the box! I'm no artist, but I do believe that with the proper training and lots of practice, anything is possible!
Yesterday, I learned (for the first time) about the (new) variable width stroke tool. Way, way, way cool!!!