I've been playing bass guitar for nearly four years. I've never received any proper, formal lessons. I've purchased several books and have read countless articles on the internet. Now, I'm looking for some visual instruction. Can anyone recommend a suitable DVD for someone who is beyond the basics, and is looking to expand in all other fields?

Billy Sheehan is planning on bring out a new/re-issue instructional DVD. I have the first VHS video, which is mostly about soloing. I have Jaco on VHS, which is also avaliable on DVD, is worth checking out. Other VHS instructional video that I have include:
-Two-handed Tapping For the Bass w/ Kjell Benner - has a lot of theory stuff
-John Entwistle instructional video
-Stu Hamm's first video
-Flea's instructional video - avaliable on DVD

I remember reading years ago that "The Slap Bass Program With Alexis Slarevski" was one of the best instructional videos around.