Good evening Harry,
I live in the North of Ireland, near Belfast so I am not familiar with the west of Ireland (near Shannon), try this link
http://www.sea-angling-ireland.org/map% ... 0shore.htm
and click on the County that you are staying in. It will give you some idea of the best marks to fish.
Most shore anglers in Ireland use 15lb (0.35mm) or 18lb (0.40mm) line for fishing from the beach with at least a 50lb (0.90mm) trace line combined with a 4oz (150g) or 5oz (175g) sinker.
If you are targeting ray you will need at least a 3/0 hook, for baby sharks (tope etc.) you will probably need a strong 6/0 O'Shaughnessy hook.
Best baits to use are mackeral, sandeel, squid or lug/rag worm. Most of the baits can be bought in the local tackle shops.
The Abu Ambassadeur reel is fine for beach work but you will need something stronger if you want to fish rough ground (Penn 525 or Diawa SL30SH). You can expect to catch good pollack, wrasse and bull huss over rough ground near the River Shannon.
Good luck and let us know how you get on.
GG