Ebay is... ok. I am skeptical of everything ebay partially due to some of the swords I have seen on there.
First thing is look at celtic croft sinc eit is a link at teh top of every page. Another thing is to do a google search for "4 yard box pleated" which will send you to Matt Newsome's (a major poster here) site where he makes kilts similar to the original tailored kilts. Somewhere that I have heard very good reviews about (in customer service, product, and as people) is www.kilts.com. The real world location is actually less than 2 miles from my house. For a formal kilt (and the rest of the outfit) look at Hector Russle. A low cost option for a wool kilt is www.Stillwaterkilts.com's wool heavyweight. Barb T. on this forum, the author of "The Art of Kiltmaking", makes good kilts. Bearkilt makes good kilts though last I heard he had a big backlog (a testament to his skill).
I have been recomended to Josh Amos at Neokilts and have talked to him via swordforum.com though my e-mail killed the message he sent me that listed his prices.

Those are all the wool kiltmakers that comes to mind at the moment. I know I missed a couple of good ones, but I have only been at this about a month.