when I was first intoduced to the Mercer area, we used to stay at Pine Forest Lodge every trip.
The fishing wasn't easy for the first ten years or so, but we eventually figured it out. I suspect you don't have that much time to waste, so here are a few hints.....
Walleye: jig and crawler/ worm/ minnow/ or even Gulp. we anchored just outside the thick cabbage weeds and casted in.
Try around Doctor's point (has the big satelite dish). Also look for the large laydows sticking off the shorelines.
smallies: shoreline is always a good bet in early June, however don't overlook the rock bars. Again, any laydowns along the shore too. Jig, slip bobber, or my favorite : top water!
panfish: I'm not sure if it is still there, but there used to be a crib between the green beaver island, and the shore closest to it (green beaver is the island closest to Pine Forest Lodge).
There are also a number of cribs in the bay that the lodge sits above.
As for the muskies.... don't overlook throwing at the river mouth that leads to the oxboes. That area always produced for us.
I hope this helps, or even holds true, as I havn't fished Spider in 10 years or so....... you know.... since I started my love affair with the flowaga.
chris