For the last several years, I have been buying my Parmigiano-Reggiano in large chunks, and then grating it myself. Believe it or not, the Costco in my area sells fairly decent Parm at a fairly reasonable price. It will seem expensive and will probably run you at least $25.00 for a good sized wedge, but remember it will last a few months (mine does anyway), and lest we forget that those lovely green plastic containers are usually at least $8.00 at the grocery store, so you are buying a far superior product in bulk (Costco doesn't do anything small) and with minimal labour required at home to grate it.
Now, if you want to, you could seek out a specialty cheese shop, and buy a more expensive brand, with maybe a more distinct flavour, but at the end of the day I do have a grocery budget for my family, so the brand at Costco works for me - and it does fit my criteria (when in doubt make sure the rind of the cheese is stamped with the signature "label" that it has been produced in Italy), not to mention it tastes pretty darn good and makes "real" cheese accessible to everyone!I personally like to grate my cheese in two "consistencies". I like the finer, powder like grate for sauces, or stirred into soups because it will melt quickly and easily. But, I also prefer a more typical grated cheese to sprinkle over pastas and salads, grilled veggies or pizza.
For the first, you'll need a pretty heavy duty food processor. The first few spins will practically send the whole thing careening to the floor, so I can only imagine the damage this uber-hard cheese would do to one that doesn't have a fairly sturdy base and motor! Simply cut half your wedge of parm into a few large chunks, place in food processor, and whirl until sand like consistency forms.
For the latter, well, let's just say you can skip your arm workout that day. I don't have a grater fine enough on my food processor, so I end up doing this one by hand. It takes a few minutes, and you may break into a sweat, but just keep reminding yourself just how delicious your next batch of spaghetti will be!
And Voila! Several containers of grated, fresh, REAL Parmigiano-Reggiano for your epicurean adventures. I store the smaller containers in the fridge and the larger ones in the freezer, refilling the smaller ones as they run out. Do remember that a little goes a long way, so it really should last you at least a couple of months. Trust me though, the effort (and the slightly elevated cost) will be worth it. You'll never go back to that pre-packaged stuff again (and your belly will certainly thank you!)