Lee Brimelow's Flash Video Basics series at http://library.creativecow.net/video-tutorials/adobeflash is for Flash MX (2004). Will there be new tutorials for people using CS4? Or a written page showing how CS4 users should modify the lessons from the tutorial? I'd guess that the original code still works, but some of it is pretty laborious, and I wonder if CS4 has built-in pre-sets that make [coding] more efficient.
Tutorials written for Flash MX 2004 will be (probably) using ActionScript 2.0. You can write this version of AS in Flash CS4 if you wish, but you can also use a new version (ActionScript 3.0), which is different. It largely depends on which version of AS you want to learn (I'd recommend just starting with the latest). There are a lot of tutorials around on AS3, and even a number that use Flash CS4 too so you won't get confused by the different UI's. Lee has some up on his site, gotoandlearn.com. There are also others on the adobe.com website (look for Adobe TV).