If the server has already made the entire map, why wouldn't you simply push a small section of map to the corresponding user(s).
Sending a 'seed' to the client so that it can generate its own map is dangerous because your actually relying on *trust* with the client.
Well, actually, it's no more dangerous than sending the entire map (or having it included with the client download).
If you want to limit the visible area to the player, send a unique seed for every n*n tiles.
Just make sure that the server double checks that the player really could pass that wall, and that the player really could reach that item. (But you have to check this regardless of if you send the seed or the actual map)
As for the original post:
I've been interested procedural content for a while now, and my best advice is probably to just draw a map on paper, looking roughly how you'd want the generated maps to look, but think about HOW you draw it. If you start by adding a huge room, then adding corridors from that and smaller rooms at the end, then that might be a good way for the algorithm to work.
There are some articles in the roguelike news archives
, of varying quality.