Here (might need to reappraise my opinion of the 'tedious descriptions of smithcraft' though...) and the second series over Here.
These books can be found on Amazon (ridiculously cheap) and I'd always recommend them. The other day, I was told that SF Gateway will be publishing the first two books ('The Anvil of Ice' and 'The Forge in the Forest') as ebooks early next month. Thanks for the heads up Simon! ;o) Shame they're going for the plain yellow cover rather than the gorgeous Ian Miller originals though.
I'm a self confessed fan of these books but they are worth the read anyway, no doubt about it. It's long past time I had a re-read so I'll be picking up 'The Anvil of Ice' and 'The Forge in the Forest', aiming for reviews in early November. You Kindle owners could do a lot worse than head over to Amazon and grab yourselves copies (£2.99, if I didn't already have second hand copies then I'd fork out the cash).