sol's now at the second dungeon fyi
you're supposed to work your way through that mini dungeon.
from where you said you were, go stright on, open the stone door (if its not already open) and go in
if you try it out, it should be quite obvious how it works. but you just need to advance to the next floor. on the 3rd one. you have to get triforce looking things from chests and put them in the place shown.
then, once you get out of there, just get the map from the chest, go right and warp out
then, go to the middle island (not the island you start on or the first dungeon island) and speak to the man in the shop. follow him to the gate he opens. find your way through there, eventually coming to some blocks you must blow up to get back into that shop from the other side.
then, you'll get a nice new toy. you can use it to go to the left hand side of the map. but then, you'll see what to do, naturally, and then end up sailing around thinking wtf do i do now? like i'm doing. but i may be onto something. i'll start playing again in a bit and update my guide on page two that already says all of what i just said >_<
edit: ok, the guide (on page 2) has been updated as much as it will tonight. i'll continue it tomorrow.
it'd also be cool if any of you that may be using it could tell me if you're finding it useful and what other info you'd like in there etc? ^^