I use an audio interface with bookshelf speakers... mostly overkill for people who don't make music because they have xlr and line level inputs for using a professional mic.
Do you have room in your computer setup for two bookshelf speakers at ear height? Because otherwise, I'd recommend a sound bar type of deal.
Klipsch has been a consistently good brand for a long time. I checked on ebay and there's some great ones for $200 to $300. Only 2.0 setups for that price, though.
You will need an amp for those unless it's got a built-in amp (some models have that).