In reply to alitamlit: Having studied at Uni there for a number of years, and been an active member of their mountaineering club, I can safely say there's not a lot worth doing south of Cadair Idris. The best route near to Aber is probably Cyfrwy Arete if you climb easy, or if you climb hard E grades just head to Tremadog.
Enjoy finding somewhere; I had many frustrating days of not being able to find transport to get north but if you have a few days in a row the bus service is superb value for money (X55 from the train station gets you all the way to Bangor via Porthmadog (i.e tremadog area)).
Alternatively head south to Pembroke/Gower. Barmouth slabs not really worth bothering with, and any bouldering is pretty uninspiring.
Get to Plas y Brenin if you want to go on a course, or look on the Mountain Training Association website to find a qualified instructor. There are a few near to Aber.
cheers, hope that helps.