What type of home theater system will i need?

Ok i want a decent but not expensive home surround sound system that play's my TV audio and where i can also hook it up to my computer when i want to listen to music and watch Netflix, is there a certain type i need to get? does not have to be like those 1 thousand dollar systems just something mildly cheap that gives good sound since i already have a sub woofer i need some speakers and a receiver (i think )