Car insurance

Does anyone have any experience buying a car and obtaining car insurance with a US driver's license?

Just starting the process in Sligo. 

A US license won't transfer, but you can drive on it for 12 months. 

Checked on insurance today, unless I can get my US-based car insurance company to write a letter saying that I've had no claims in five years, then my insurance will go from 650 Euro to 2,500 Euro!  Also, it will take six months and payment for driving instruction to get an Irish drivers license. Not what I expected. Best case scenario: insurance 650 plus motor tax of a similar amount for a smallish/midsize car each year.

I might just use taxis and trains instead and forget a car.