Shoes are built over a form called a last. Since you first pull the leather/fabric tight over the top of the last and then attach it to the sole, the shape of the last directly informs the shape of the resulting shoe. If you want to create a pointy-toed, high-heeled shoe, you’ll need a pointy-toed last shaped for the desired heel height. And if you want to make a size 9 wide shoe, you have to use a size 9 last—a size 6 won’t fit—and you might have to modify it to make it wider than it is. As they say, the last comes first.
Built to last–there’s another little pun courtesy of shoe makers. One more: Lasting impressions. Groan.
Lasts are hinged so that when you’re finished making the shoe, you can get the last out from inside it.
You can find lasts on ebay, of course, but that’s not the place to go if you want an entire run—every size in every width for a given model. I’ve bought new lasts from Jones & Vining, and used lasts from Shoedo.com and George Barta Hide Company. I haven’t yet gotten lasts from Dick Anderson, but I’m told he’ll let you get a pair on trial to see if they work for your needs. I’ve also come across Shoe Last Shop online; I haven’t ordered from them but via email they said they have many more styles available than are present on their website.