Cheese – Can cheese be sculpted

By the wording of the question, I'm pretty sure you're using one of those pyramidal graters or a "sheet" grater.

That's great for getting the "bulk", but if you want to grate a small amount of cheese (or the last bit of a large amount, if you don't want to just eat it) then you really need to get yourself a rotary grater. They're more commonly used for fine/hard cheeses such as Parmesan, but most half-decent ones will come with a "coarse" blade that can be used for cheddar, mozzarella and so on.

Rotary graters all have a plate at the top that lets you push the cheese down onto the blade. Higher-quality graters will give you slightly better results; the $10 cheap ones tend to leave a mush at the bottom that's hard to grate, even if you squeeze really hard, but that's easily remedied with a small wooden block or really any object at all to put between the top plate and the cheese you're trying to grate.

I'm not sure that's the right way to go about this. There are tons and tons of types of cheeses. I'm not sure you'll find a good list of all substitutes because it will be too big to put together.

Instead, I think you need to learn about the types of cheese so that you can make an informed decision. Is a cheese blue, sharp, creamy, hard, soft? How does it melt? What part of the world is it from? Those questions will allow you to find a cheese that is similar enough to make a good substitution.

For instance, if a recipe called for Pecorino a hard Italian cheese, Parmesan (another hard Italian cheese) would make a much better substitute than goat cheese or cheddar.

So see what cheeses are available at your local store. Write down the whole list (and preferably buy some of each). Get home and do a little bit of research on each one. Where is it from? How do people describe it? Take some notes on all of this. Then, when you see a new cheese in a recipe, look it up and see how it's described. Then find a cheese from a similar area with similar characteristics, and you should be good to go.

Edit: While I stand by my approach as a great way to go about this, I did find a good resource. Cook's Thesaurus has a great list of cheeses, including substitutes, broken down by type of cheese, type of milk, hardness, etc.