Hello Bruno (and any newcomer),
Like yourself I started fishing again in the last while. I have deffo come to the opinion that I'll avoid buying expensive gear until I find fish that require me to do so.
I have a light, inexpensive spinning rod, with a E40 Okuma reel. Since last summer I have caught dozens of mackerel, scad, pollack (to 3.5lbs), coalfish, wrasse (to 5lbs) on this rod alone.
If you get out in the next couple of weeks (Youghal, Monkstown, Kinsale etc.) you might catch a few mackerel before they're gone. That'll remind you of why you want to get fishing again
You would need a different set-up for bottom fishing, this is where I plug a book that gave me a great basic knowledge for sea fishing,
"Sea Fishing Properly Explained", it's part of the 'Right Way' series of books, they have a very good website -
http://www.right-way.co.uk if you can't find it in a shop (I picked it up in Easons).
In that book you can get details of knots to tie, rigs to use, tactics to catch different species. It's quite basic but full of useful info that you can study quietly before you go fishing.
Then the biggest pool of knowledge you'll find is on this website!!!
Good Luck
Blackie