If you happen to be in Edinburgh you might want to check out the Celts Exhibition at the National Museum Of Scotland. There are loads of famous Celtic finds on display and these are complimented by informative films and the usual multi-media fare.
I was blown away to see the Gundestrup Cauldron there. This is such a beautiful piece of work and the designs are amazing. To see it there, in the real, choked me up with emotion. Very impressive. There are numerous other items I am very familiar with on exhibit. I have sketched designs from many of these objects into my books over the years. It was kind of like seeing old relatives... you know what I mean... there was a certain familiarity, even though I've only seen most of them in books. They felt like old friends! Some of the designs on display I've even carved at some point over the last twenty years!
The only bone of contention is that photos aren't allowed. This seems to be a bit of a liberty (or less liberty), but perhaps it's an attempt to secure sales of the museum catalog (a hefty £25 each). But apart from that the content is well worth the tenner entrance fee. So go visit, and then, once you're all fired up and inspired you can came on down to Playfair Steps (near the National Art Gallery) and visit my stall (hidden amongst the cheap Thai silverware and faux Celtic offerings), there you'll find my hand carved stones! :>