If you really want to know how to play Stud-8 well, Ray Zee's book is the definitive guide. I have been playing (mostly MTT and SnGs) for about three months now and I love it! I would play more, but I discovered 8-Game on Poker Stars
, and just can't resist it!
When playing on a full table you definitely need to be very selective with your starting hands, and know how to play them. Like skollpada says, don't play Razz hands (but if everyone is showing high cards only you could). You need to be trying to build a hand that will scoop, and you can only do this by playing a hand that can win both ends. This would include an Ace with two low cards, three connecting low cards that will make a straight, two low and one high to a flush, pair of Aces with a low card, low pair with low kicker.
High only hands such as good pairs and trips can be played (and should be played when the game is shorthanded i.e. four players or less), but you will have to be aggressive with them in order to eliminate/extract calls from the low draws.
I like to take the very tight/ultra aggressive approach: I will almost always start with a top class scooping hand, and if I hit good to my hand on fourth I will be betting/raising all the way to seventh, and will be firing on seventh even if I miss. I have tried a more conservative play beyond fourth, but that doesn't work for me - I think it's correct to be betting your good drawing hands, and at the limits I play at ($1- $5) it works well enough. This is possibly because at this level most of the players are more 'recreational', and out to have some fun, as opposed to wanting to play a killer game.