gbear,
Everyone has access to every golfer every week. There are 3 lists of golfers: you pick a certain number from each list (it's between 2 and 4) each week (they usually tell you who is entered in the tournament for that week so you don't pick guys who aren't in the field). From that number, you "start" half of them (if list A has 4, you start 2). At any time, you can switch to your other golfers on the bench during the week. So, if you have Tiger and Kenny Perry from List A, and you have Tiger starting and he shoots 80-80 the first 2 days, you can switch to Kenny Perry at any time. You accumulate points each day based on the best score for the day, and then get bonus points at the end of the weekend if your guy finishes 1, 2, or 3.
The catch is that you can only use each golfer 10 times, and if you switch between golfers, it counds as "1" for everyone you use, even if it is only for 1 round. If you leave guys on the bench and don't use them, it does NOT count towards your 10.
I'm making it sound more complicated than it is...it actually only takes like 2 minutes to check in on the leaderboard and make any switches, so it really is fun and pretty low maintainence. You should give it a try.