I'm guessing you've just started looking out for a home theater system. So right off the bat, let me tell you that buying a home theater is not like buying a television or a refrigerator where you look at a model, get some opinions, then go out and buy. A home theater is not so much as bought as it is built. And you have to be careful about every aspect of it.
I am not sure what is your current level of understanding of an HT system, so some of this information might be redundant. An HT has the following components
Audio Video Receiver: Commonly referred to as AVR, this is the brain and heart of the system. All speakers connect to it and it drives all the speakers. It contains the chips to decode and process audio signals and amplifiers to send power to the speakers. Typically, you'll also connect your video sources to the AVR and then output cable will connect your TV to your AVR
Front Speakers: These are the front left and right speakers (1 pair), placed beside your television
Center speaker: This speaker is generally placed below the TV, but can also be placed above.
Surround speakers: These speakers (1 pair) are placed slightly behind, or beside the seating position of the viewer, depending on space availability
Atmos Ceiling speakers (optional): These speakers (1 pair) are placed on the ceiling and are optional.
A typical HT setup is known as 5.1, 5 speakers + 1 subwoofer. A setup with ceiling speakers is known as 5.1.2, 5 ear level speakers, 1 subwoofer, and 2 ceiling speakers.
Now with that out of the way, let me come to the actual system. The first thing you need to decide is whether you want to go for 5.1 or 5.1.2, because budget and recommendations will vary a lot between the two setups. You also need to tell us the layout of the room, what will be your viewing distance, etc. So that we can understand the requirements. Finally, availability varies a lot across our country, especially these days. Building an HT system is easiest in Bangalore, followed by Chennai (mostly), can get progressively harder in other cities and smaller cities. Buying online is not really recommended, unless you're absolutely sure you know what you want. So for us to suggest where to buy, you need to tell us your location.
It will also help if we were to know what kind of experience you have currently with audio systems. Have you been using regular, off the shelf speakers, good quality bookshelf speakers, or just TV speakers?
Lastly, audio preference is very personal. So it is not recommended to buy based on others' recommendations alone. You should shortlist based on recommendations, then find vendors in your town who'd be willing to give you a demo of the speakers you've shortlisted. Speaker demo is not very uncommon and a lot of vendors offer it. So don't be afraid to ask for a demo.
P.S.: I've just bought an HT on a tight budget and am yet to receive some of the components, so this journey is very fresh in my mind.
