Docy,
I used a crowd in Ranelagh village, €70 for a pretest that lasts about 1hr 30min's. Expensive but probably worth it, he will teach you the technique to passing the test which is a style of driving that is not only useless but impratical, having said that you need it to pass the test. In churctown you won't have any need to exceed the 50kmh limit, best piece of advisce I recieved form the instructor was that they are looking for competent, confident "drivers" - not learners sitting their test. Remember, Mirror, Indicate, Manouver.
Anyway, good luck!!!
Sambo