Our home office (my mrs and I both work from home at times) has a 2 metre long ikea Vika table top each, with a mix of drawer and shelving units as legs.
We have cheap monitor arms (like this but black. If it was 3×24″ though I’d get one designed for three monitors, ideally wall-mounting if that’s an option. Ikea do great cable management trays that screw to the underside of the desk too, we have a couple so a big powerstrip each lives in there along with power adaptors, excess cable, etc. Keeps it nice and neat and away from your legs.
For the speakers, I’d look to specialist stands or just get the little wooden drawer units to put them on – gets some more storage on the desk for cables and other odds and sods.