Fortunately now we have 2 dedicated Health Insurance Companies in India.
1. Apollo DKV Health Insurance
2. Star Health Insurance Company
Both of them are focused Health Insurance companies, hence they are good both in terms of service and products. Yea, premium are little higher but they are good.
Besides then, all General Insurance companies in India provide health cover.
Dont get confused with Life Insurance companies like LIC or ICICI Pru health initiatives. They are focused Life companies, hence better to buy either from Apollo / Sta or General Insurance companies and not Life Insurance companies.
If you want options, then try Bajaj Allianz General / ICICI Lombard General and Oriental Insurance company.
If you dont want to chase different agents from different companies for your Insurance Policy and want all under one roof, then best bet is India's first On-line Insurance Portal - http://www.InsuranceMall.in
At this site, you could compare and buynow your choice health Insurance policy at your pace.
For critical reviews on all Health Insurance products in India, you may want to read Bonsai Insurance Blog - I Opener at www.InsuranceMall.in/blog