What is the best affordable rain gear for a trip to Ireland and Scotland?

A couple of years ago I bought a rain jacket & pants set, brand name Frog Toggs at a sporting goods store for around $25. They are very light weight, fold up small, and do a decent job shedding rain. I've never stood in a drenching thunderstorm-type shower, but they are fine for keeping at bay the constant drizzle we often get in Seattle. I believe they use a generic version of DuPont's trademarked Tyvek which is essentially a non-woven polyethylene fabric. I can't speak to the ability to pass moisture rather than hold it inside the fabric, which could be an issue if you are moving enough to generate perspiration. From what I've seen of Irish spring time rain, I think it would be acceptable if you won't be outside for long stretches. Be aware that it won't hold much if any body heat, especially in the wind, so you will likely want some insulating layers underneath depending on the temperature. Enjoy your trip.

I swear by a jacket with a hood and a rain hat with a brim that I wear under the hood. This combination keeps as much rain off my face as possible. Sierra Trading Post, LL Bean, and Lands End are reasonably priced sources.

You do have boots, right? (heh heh) Spray your boots well with silicone waterproofing spray before you leave home. And get a can of Scotchgard and spray the upper portion of your jeans and other trousers, between where the boot tops leave off and the jacket hem begins.

Do not buy a poncho or an umbrella. Sideways ("lashing") rain makes these fairly useless.

Are you planning on doing a lot of hiking or biking? We were in Ireland last July and were fine with just a north face/columbia type rain coat. The only time I wished I had rain pants is when we went on a 2 hour horse back ride and it was a massive downpour the whole time.

Thanks all! We will be in Ireland and Scotland the first two weeks of June. It looks like I have some shopping to do :)

If you have an REI near you go look there, try stuff on and see what you like. Then go home and look for it on the aforementioned Sierra Trading Post!! Also if you have a Cabelas see what's on sale.

My brother has Frogg Toggs and they are completely waterproof as he has stood out in downpours with them on but they are pretty....um...oddly shaped.

I would not bother with rain pants unless you are hiking long distances every day.

In addition to the Frogg Toggs mentioned earlier, here are 3 highly rated jackets:

Marmot PreCip Rain Jacket $60 on Amazon
Columbia Watertight II Rain Jacket $45 on Amazon
Outdoor Research Helium II Rain Jacket $100 - $150 on Amazon