Hi Frank, already a lot posted on gear, a quick look through recent topics should give you all you need.
This Forum has more(Up to Date) info in this section than books and DVD's currently out there. You'll also get reative advice.
Saltwater Flyfishing - Paul Morgan and Friends
Hooked on Bass - Excellent learning on bait behaviour and terrain etc.
Flyfishing with a pinch of salt - Mike Ladle and geoff hancock
OS map and tide table.
Notebook and pen
You have awesome fishing around you - just go to sea and start the journey. You wont get marks on a public forum and people will just close up on all info when people push for them. Doing well at SWFFing in this country requires legwork and effort. The results are far more rewarding and as people get to know you and trust that you wont share their marks then you will fish with more and more people. It's sad that thats the way but unfortunately due to fantastic Fishery management

it's just the way it is.
"How do you know where the fish are?"
By doing what you are about to :-) Read this forum to get advice on tides and flies etc. Study OS maps looking for structure, rivers bays and tidal flows. Go down to the coast and fish those at different locations at different states of tide and times and wind directions. All fish differently. Luckily the fish are mobile and you will run into them. You'll figure out the locations then start catching reguarly. Take notes and record your outings.
Good luck - keep asking questions and applying the answers