I am wondering in order where should I start in updating my front and rear suspension. I have a 68 LeMans (I know it's not a Chevelle, but it is GM A body and does have Chevy 454 in it) The suspension and brakes are 100% stock, it has non power drum brakes, and a 10 bolt rear end. What I am wondering is, I would eventually like to upgrade the entire suspension but a need a place to start and some recomendations on what to use. Any suggestions are appreciated.

I would start with the front suspension and brakes, since the fronts do 85% of your braking. Don't mess around with the drums, upgrading to discs is easy, affordable, and work so much better.

There's good information to get started in these 2 links:
http://www.chevelles.com/forums/showthread.php?t=107745

http://www.chevelles.com/reviews/showproduct.php?product=122&sort=7&cat=21&page=1