I've just received the new Darts Corner Catalogue for 2010 and the stock they carry is amazing. I've used their web site before but because I was just searching for the specific items I was interested in I didn't appreciate their full range. For example, I didn't even know that those "real feather" flights were still freely available, but at Darts Corner you get a choice of shape, colour, and 2BA / Qtr Inch threads. Here's an example.
One slight thing they may want to improve upon is to give bulk discounts for flights and stems, because I can't see any sliding scale costs based on quantities as you get with Tommy's Darts, and 10 of my favourite Ruthless R4X flights look a little more expensive with DC than with TD. If I were to order 50 sets it would be a 30% difference unless there is a bulk discount I can't find in the catalogue?
This is a very minor point though, and their product range matches anything I've seen. All of those odd little hard to find things are covered in their catalogue - in detail and with choices. Also, they were one the first companies I noticed to print the specific dimensions of the darts rather than just the weight and tungsten ratio. They handled my last order well and I'll definitely use them again. Try search words of "shirt" and "trophy" on their site as two quick examples of what they offer, and then try the same search words on other sites. It's the same for those hard to find things I mentioned.