For whitley the bigger the sea the better, and i find it best to start at little bay(if you park at the cafe in the middle of the beach and walk north up the prom till the end, its roughly in line with the end of the prom) and work your way down the beach till you find the fish. Big tides are best so you can access the skeers, but too big and most the marks will empty out. 3 hours down and 1 up i find fishes best. Have a look on nesa homepage in the northeast marks section, theres a good map of whitley beach in there.
The pier's quite easy to get onto, afew different ways to get on, easyest seems to be if you go up the ramp walking towards the peir and climb round that fence(river side) by steping ontop of the spikes, you can do this on the lower section aswell but abit trickier.