Herbs:
    fresh coriander (cilantro)
    fresh mint
     These are best if used fresh, but ground or powdered
      forms will suffice if the fresh is not available.

Roots:
    onion
    garlic
    fresh ginger (or ginger powder if not available)

Spices:
    Garam masala powder (curry powder)
    Denia power ()
    Haldi (tumeric powder)
    (dried mango powder)
    Hing (Asafetida)
    Chilies (fresh green or red, dried)
    Lal mirch powder (red chili powder)
    (cumin seed or powder)
    (cloves)
    Imli (Tamarind)
    Rai (mustard seeds)
    Coriander seeds or powder
    Kadhi patta (curry leaves)
    Methi Dana (feugreek seeds)

Dals
The staple of the Indian diet is rice and Dal (lentils). As the Indian diet is primarily vegitarian, the various dals provide an excellent source of protiens and nutrition. There are actually scores of different dals with a wide variety of tastes. Some of the most common are:
    Moong dal (green)
    Moong dal (yellow)
    Chana dal (chick peas)
    Rajma dal (kidney beans)
    Black urad dal

Common vegatables
    Tamater (tomatoes)
    Alu (potatoes)
    Mutter (peas)
    Gobi (cauliflower or cabbage)
    Bangin (eggplant)
    Bindi (okra)
    Saag (spinach)
    Gajer (carrots)
    Shimla mirch (green bell pepper)

Other common ingredients:
    Cashews
    Rasins
    Paneer (an Indian dairy product similar to pressed cottage cheese)
    Ghee (drawn butter)
    Dhee (yogurt)
    Cream
    Tael (oil, sunflower oil is commonly used and is the healthiest)

Apart from the powders listed, these spices are best if purchased whole and crushed and ground just prior to cooking.