Have a load of spices and get a book about spice mixes as you may wanna make them yourself (50 Great Curries of India by Camellia Panjabi is highly recommended, also Choosing and using spices by Morris and Mackley is another good spice book) You may save money this way and by having a whole range of spice you'll always have what you need and preferably always buy whole spices.
Whole spices: heat them before you grind them in your stone pestle and mortar, this adds to the flavour. It's good to have two different sizes of pestle and mortar depending on the amount of spice you are crushing, add rock salt as an abrasive. Allspice is actually one berry it was called Allspice by the english in 1621 who thought it tasted of cinnamon, nutmeg and cloves but is actually pimento dioica- Jamaican Pepper.
You can always grow your own herbs and spices too.