a lot of folk fish down by the lighthouse not sure where tho but there are beaten tracks that you could follow, there are a lot of steep slopes there to the sea so just be careful.
also as you pass by the beach there and cross the cattle grid that says no entry go up past the first corners and as you come to the second corner just park on the grass there, you will see where cars have been parked by the grass.
just walk to the sea, keeping to the left there should be another well beaten path to it.
have a look here:
http://maps.osi.ie/publicviewer/#V1,571877,870010,6,4
& :
http://map