This list is to explain what incense you should use for which types of spells. It may not be perfect, but it is a good guideline to follow.

Acacia: Burned with Sandalwood to stimulate the psychic powers.
African Violet: Burned for protection and to promote spirituality within the home.
Allspice: Burned to attract both good luck and money.
Aloes: Burned to attract good fortune, love, spiritual vibrations and strength.
Althea: Burned for protection and to stimulate psychic powers.
Anise Seeds: Burned as a meditation incense.
Basil: Burned to exorcise and protect against evil entities (such as demons and unfriendly ghosts), and to attract fidelity, love, good luck, sympathy, and wealth. This is also an excellent incense to use when performing love divinations.
Bay: Burned to facilitate the psychic powers and to induce prophetic dream visions.
Bayberry: Burned mainly to attract money.
Benzoin: Burned for purification and to attract prosperity.
Bistort: Burned (often with Frankincense) as a powerful incense to aid divination.
Bracken: Burned in outdoor fires to magically produce rain.
Blue Berry: Burn to keep unwanted influences away from your home and property.
Blue Roses: Specially crafted to honour the Goddess in all her aspects.
Carnations: A sweet floral scent traditionally used for healing.
Cedar: Burned for purification, to stimulate or strengthen the psychic powers, attract love, prevent nightmares and heal various ailments including head colds.
Cherry: Sacred to Venus, this blend will attract and stimulate love.
Cinnamon: Use to gain wealth and success.
Citron: Burned in rituals to aid healing and also to strengthen the psychic powers.
Clove: Burned to dispel negativity, purify sacred and magickal spaces, attract money, and stop or prevent the spread of gossip.
Coconut: Burn for protection and purification.
Damiana: Burned to facilitate psychic visions.
Dittany of Crete: Burned to conjure spirits and to aid in astral protection (especially when mixed with equal parts of Benzoin, Sandalwood and Vanilla).
Dragon's Blood: Burned to dispel negativity, exorcise evil supernatural entities, attract love, and restore male potency. Many Witches also burn Dragon's Blood for protection when spell-casting and invoking. When added to other incenses, Dragon's Blood makes their magickal powers all the stronger.
Elecampane: Burned to strengthen the clairvoyant powers and scrying (divination by gazing) abilities.
Fern: Burned in outdoor fires to magickally produce rain, also used to exorcise evil supernatural entities.
Frankincense: Burned to dispel negativity, purify magickal spaces, protect against evil, aid meditation, induce psychic visions, attract good luck, and honor Pagan deities.
Fumitory: Burned to exorcise demons, poltergeists and evil supernatural entities.
Galangal: Burned to break curses cast by sorcerers.
Ginseng Root: Burned to keep wicked spirits at bay, and for protection against all forms of evil.
Gotu Kola: Burned to aid meditation.
Heather: Burned to conjure beneficial spirits, and to magickally produce rain.
Hibiscus Flowers: Burned to attract love.
Honeysuckle: Burn for good health, luck, and psychic power.
Horehound: Burned as an offertory incense to the Ancient Egyptian god Horus.
Jasmine: Burned to attract love and money, and also to induce dreams of a prophetic nature.
Juniper: Burned to stimulate or increase the psychic powers and also to break curses and hexes cast by evil sorcerers
Lavender: Burned to induce rest and sleep, and to attract love (especially of a guy).
Lilac: Burned to stimulate or increase the psychic powers, to attract harmony into one's life.
Lotus: For inner peace and outer harmony, to aid in meditation and open the mind's eye.
Mace: Burned to stimulate or increase the psychic powers.
Mastic: Burned to conjure beneficial spirits, stimulate or increase psychic powers, and intensify sexual desires. The magickal powers of other incenses are greatly increased when a bit of Mastic is added.
Mesquite: The magickal powers of all healing incenses are greatly increased when Mesquite is added.
Mint: Burned to increase sexual desire, exorcise evil supernatural entities, conjure beneficial spirits and attract money. Mint incense also possesses strong healing vibrations and protective powers.
Musk: Burn for courage and vitality, or to highten sensual passion.
Myrrh: Burned (often in Frankincense) for purification, consecration, healing, exorcism, and banishing evil. Myrrh also aids meditation rituals, and was commonly burned on altars in Ancient Egypt as an offering to the deities Isis and Ra.
Nutmeg: Burned to aid meditation, stimulate or increase psychic powers and to attract prosperity.
Passionflower: For peace of mind, this sweet scent will soothe troubles and aid in sleep.
Patchouli: Burned to attract money and love, and also to promote fertility.
Pine: Burned for purification, and to banish negative energies, exorcise evil supernatural entities, and attract money, as well as to break hexes and return them to their senders.
Poppy Seeds: Burned to promote female fertility, and to attract love, good luck, and money.
Rose: Burned to increase courage, induce prophetic dreams, and attract love. Rose incense is used in all forms of love enchantment and posses the strongest love vibration of any magickal incense.
Rosemary: Burned to purify, aid in healing, prevent nightmares, preserve youthfulness, dispel depression, attract fairy-folk, and promote restful sleep and pleasant dreams.
Rue: Burned to help restore health.
White Sage: Burned for protection against all forms of evil, and to purify sacred spaces and ritual tools, promote wisdom, attract money, and aid in healing the body, mind and soul.
Sagebrush: Burned to aid healing, and to banish negative energies and evil supernatural entities.
Sandalwood: Burned to exorcise demons and evil ghosts, conjure beneficial spirits, and to promote spiritual awareness. Sandalwood incense is also used by many Witches in healing rituals and in wish-magick.
Solomon's Seal: Burned mainly as offertory incense to ancient Pagan deities.
Spirit: Raise your personal vibration, attract spirit guides and honour your personal deity.
Star Anise Seeds: Burned to stimulate or increase the psychic powers.
Strawberry: For love, luck and friendship.
Sweetgrass: Burned to conjure beneficial spirits prior to spell casting.
Tangerine: A solar aroma used to attract prosperity.
Temple: A devotional incense for the altar during ritual.
Thyme: Burned for the purification of magickal spaces prior to rituals, to aid in healing, and to attract good health.
Vanilla: Burned to attract love, increase sexual desire and improve the powers of the mind.
Vervain: Burned to exorcise evil supernatural entities.
Vetivert: Burned to break curses, and for protection against sorcery (black magick) and thieves.
Willow: Burned to avert evil, attract love, and promote healing. It is also used by many Witches as offertory incense for Pagan lunar deities.
Wisteria: Burned for protection against all forms of evil.
Wormwood: Burned to stimulate or increase the psychic powers. When mixed with Sandalwood and burned at night in a cemetery, wormwood is said to be able to conjure spirits from their graves.

The scents in their plant form(herbs, spices, etc) are still affective and useful when not burned as an incense and usually have much of the same properties. The act of burning such herbs and spices as incense is simply to get the affects of the plant into the air and throughout an area.