Any good restaurant will be happy to find a way to serve you better. The most difficult animal product for a vegan to avoid in regards to clothing is leather. Some people will tell you that there is no reason to not wear leather, because it's just a by-product of the animal industry that will go to waste. To put this in perspective, that is more than a million cows per year. Leather is not a harmless by-product.
Leather is most common in the form of shoes, belts, wallets, and purses.
Of these, the most difficult to replace is shoes, especially dress shoes. Leather belts can easily be replaced by canvas, nylon, or plastic belts. A good source of non-leather wallets are outdoor outfitters, which sell high quality nylon wallets. Other animal-derived clothing includes wool, silk, and down. Most hygiene and cosmetic products sold in this country are both tested on animals and contain animal ingredients.