I (mostly) followed alan h.'s excellent directions (you can find them here if you don't have them bookmarked) and converted a tweed jacket from eBay into an Argyll style jacket - wore it to church on Sunday and received several compliments. Basically, we shortened the jacket, sewed the existing pockets shut, added a new top button, made epaulets, pocket flaps and gauntlet cuffs and attached them.

Things I learned from this jacket:
1) The sewing machine is evil and bad and not required to follow the laws of man or physics. My wife understands it, but I don't. She sewed the lower seam (where the jacket was shortened) with the machine, but the rest of the alterations were handsewn.

2) Tweed is a wonderful material when your needlework isn't perfect - it hides mistakes very well.

3) Using a seam ripper is a better idea than using a sgian dubh, even if the sgian is from Cold Steel and has a functional blade. The seam ripper is less likely to wind up embedded in your finger tip.

4) Thimbles keep you from poking needles into your fingers, but make it impossible to feel what you're doing. I finally had to just deal with the needles.

5) Time spent making paper patterns is time well-spent.

I'm not sure if my image host will post the picture - if it doesn't work, click here to go directly to it.