Most worship services in India commence with a brief invocation to Ganesha, believed to be the remover of obstacles and the source of good luck.

There are several modern shrines to Ganesha across the length and breadth of the Indian subcontinent, especially in the southern state of Tamilnadu. All Saivite temples bear several shrines to the elephant faced Ganesha.

All about Ganesha:

Ganesha the elephant faced God is usually worshipped first before any other worship service is carried out to any other deity. Pillayaarpatti near Karaikkudi in Tamilnadu houses an ancient temple with a rock cut shrine to Ganesha, Karpaka Vinayakar. It is rich in festivals and traditions.

The Ashta Vinayak shrines:

The State of Maharashtra holds Ganapati in great reverence. 8 of these shrines around Pune are collectively referred to as the Ashta Vinayak temples. The Siddhi Vinayak temple in Bombay is a modern shrine visited by thousands throughout the year. Vatapi Ganapati is an image of Ganapati said to have been brought back by the Pallava King during his conquest of Badami, formerly known as Vatapi.
The hill temple dedicated to Taayumanavar - Shiva of the 1st millennium CE, is popularly reffered to as the Ucchi Pillayar temple (Rock Fort - Malaikkottai temple complex) and is associated with legends from the Ramayana.

The Tiruvalanchuzhii Shiva temple near Kumbhakonam in Tamilnadu is known more popularly for its shrine to Sweta Vinayakar, said to be made of the foam of the milky ocean (Ksheera Sagaram).

Moreshwar in Moregaon, is one of the most popular of the Ashta Vinayaka shrines in Maharashtra depicting Ganapati on a peacock mount. Ranjangaon in Maharashtra enshrines Mahaganapati depicting the legend of Shiva invoking Ganesha during his battle with the demons.
Mahad in Maharashtra enshrines Varadvinayak associated with the legend of Rukmangada, Indra and the Bhadravana forest.
Girijaatmaja Vinayak at Lenyadri hills in Maharashtra is a representation of Ganesha in the form of an infant.
Ozar in Maharashtra depicts Ganapati as Vigneshwar who quelled the arrogance of the demon Vignaasuran.

Ballal Vinayak at Pali in Maharashtra is associatedwith the legend of a young lad Ballal's devotion to Ganapati.

Chintamani Vinayak in Maharashtra is associated with the legend of the Chintamani gem and Kapila Muni. Siddhi Vinayak in Siddhatek in
Maharashtra commemorates the legend of Vishnu invoking Ganesha, during his battle with the demons.

The Gokarana Shivastalam in Karnataka and the Vaidyanath Jyotirlinga Temple at Deogarh in Bihar are prominent centers of Shiva worship. Ganesha is said to have been the cause of the origin of these worship centers.

Attributes of Ganesha

The Indian system of beliefs venerates Ganesha the elephant faced God as a destroyer of obstacles and the source of good luck. Ganesha or Vinayaka is one of the most popularly worshipped deities in the Indian system of beliefs and practices.

Ganesha is revered as the son of the Universal parents Shiva and Parvati, and is always honored first in most worship services and rituals. Ganesha is also known as Ganapati, Vigneswara, Vinayaka, Gajamukha and Ainkaran.

Symbolism: The huge size of Ganapati represents the Universe (Cosmos), and his curled trunk, the symbol OM. The elephant's head is said to represent superior intellect while the snake around his waist cosmic energy. His broken tusk is symbolic of knowledge, as it is believed that it is with this tusk that he wrote down the Mahabharata, in the capacity of a scribe, when it was recited by the sage Vyasa. The mouse - mooshikam, his mount is said to symbolize the equal importance of the biggest and smallest of creatures, in the eyes of the infinity of creation Bhraman.

Ganesha is believed to have been the scribe who wrote down the text of the Indian epic Mahabharatam as it was recited by the sage Vyasa.

The Ganesa Pancharatnam of Aadi Sankaracharya in sanskrit salutes Ganapati. The tamil works of Tirumoolar and Avvaiyaar (of the 1st millennium CE), also bear hymns saluting Ganesha. So do the Tiruppugazh hymns of Arunagirinathar of the 1st half of the 2nd millennium CE. Several of the sanskrit kritis of the Karnatic Music composer Mutthuswamy Deekshitar salute Ganapati shrines all over Tamilnadu.

Several small temples dedicated to Ganapati adorn all towns and villages of south India. Most of these are modern temples. There are several shrines to Ganesha in all Saivite temples all over south India. Ganesha is taken out at the head of all processions in festivals celebrated in the Saivite temples of Tamilnadu.

Vinayaka Chaturti is a festival celebrated in honor of Ganesha, and it is celebrated as a community festival in the state of Maharashtra, where Vinayak is held in great reverence, especially in the 8 Ashta Vinayak temples in the vicinity of Pune and in the Siddhi Vinayak temple in Mumbai.

Perhaps the most ancient of Ganapati shrines in India, is the well known Karpaka Vinayakar temple in the town of Pillaiarpatti near Karaikkudi in Tamilnadu. This temple with a rock cut shrine, bearing a collossal form of Vinayakar, is over 1600 years old.

The birth of Ganesha

Ganesha the elephant faced God is one of the most popularly worshipped forms of divinity - as a remover of obstacles and the embodiment of good luck, in the Indian system of beliefs and practices.

Ganesha is regarded as the son of Shiva and Parvati (Shakti), the Universal parents, and the brother of Skanda.

Legend has it that Parvati, created a beautiful boy from the dirt of her body, treated him as her son, and gave him the responsibility of guarding her home.

Shiva, upon returning home was affronted by this lad, hitherto unknown to him. The lad, true to his word to his mother, refused to let Shiva into his own home. An enraged Shiva sent his Bhuta Gana attendants to scare the lad and to obtain entry into his own home.
The lad single handedly defeated the Bhuta Ganas in battle. A clash of egos followed, as Shiva sent several of the Gods, to fight against Ganesha and an equally enraged Parvati sent several of her attendants to fight them. In the resultant fight, the valorous lad's head was chopped off by Nandi deva, and the lad lay lifeless.

Parvati's grief knew no bounds, and Shiva sought to assuage her, by promising to bring the boy to life. Alas, his head could not be found in the battlefield. A quick fix was sought, and it was decided that the first available head would be used to bring the boy to life. Accordingly, the boy was fitted with the head of an elephant and brought back to life.

Even this did not placate Parvati, who sought that this boy (who  successfully created obstacles to his father's mission) now fitted with the head of an elephant, should be regarded by one and all, as the remover of obstacles, and should be offered worship first, before any form of worship was offered to any other manifestation of divinity.

This boon granted, Ganesha, the lord of the attendants of Parvati, came to be regarded as Vigneshwara the remover of obstacles.