There are two temples in Karnataka to worship or offer pooja for Sarpadosha parihara. The most prominent temple in Karnataka to worship in connection with sarpadosha, rhau kethu dosha etc is the Kukke Subraanya temple. It is near Dharmasthala. From Mangalre it is about 105 km. The Bemgaluru Msangalore Railway linee passes through this pace and there is a station by same name. The main deity is Karthikeya in the form f snake god.
Another temple is Ghati Subramanya. This is near Doddaballapur and is 60 kms from Bengaluru in Bangalore rural district. Buses are available from Doddaballapur. Here the main deity is Subramanya and Narasimha.
There is also a Subramanya temple in Ramanathapura near Srirangapatna which is supposed to be similar to Kukke temple and the deity is supposed to be same.
As to other places Kerala is having the Mannarassala Nagaraja temple and exclusive temple of snake gods. It is near a town called Haripad (Pada of Hari)near to Thiruananthapuram City of Kerala. Another snake temple is Pampumekkat Mana. It is the house where the Nagaraja prathista is there which is supposed to be very powerful. This is near Ernakulam. Another place is Pambaady snake temple in Thrissur District of Kerala near Thiiruvilwamala temple.
In Tamil Nadu there are several temples for doing pooja for Snake gods. There is an exclusive Rahu temple known as Thirunageswaram near to kumbakonam town. Thirupambaram is another temple with Pambureshwar /Shesha preeswar deity supposed to be rahu and kethu together. One more where rahu and kethu in one place for removal of sarpadosham is Sreevanjiyam near kumbakonam.In Tamil Nadu there are several other temples where it is claimed is remedial for sarpadosha.
In Andhrapradesh the temple in Kalahasthi near Thirupathi is famous for sarpadhosha parihara.
Hello Mr.Balaji, Kukke Subramanya temple is in the western Ghats of Karnataka,about 105kms from mangalore and Mannarshala temple is the largest snake temple in kerala which is located at 32kms from the south of Allapuzha