It would be cool if you could look at replays of people on the ladder, but until that happens can you download other people's replays? Is there a repository or something?
TeamLiquid has a big SC2 Replaythread, also a good place to talk about reps.
If you want to study replays and analyse them I suggest the youtube channels of hdstarcraft and huskystarcraft. They upload commented games with a bit of analyzing and also provide some tutorials. For a deeper game analysis I can recommend Day Daily episodes.
The sites metioned by Michael are also great resources ;)
GameReplays.org has a Starcraft II section. I think anyone can join and add their own replays so it's not focused on "pro replays", but I'm sure there are some very good ones on there. They have an "expert replays" section, but there's nothing in it yet.
There's also SCReplays.com that has the same "host your replay" philosophy.
I think you'll have to wait a while before one definitive source comes for expert replays, since the game is so new. I doubt anyone went to the trouble for the beta.