rodgers942

I currently have an 8" sub and two 12.5 bookshelf speakers (all klipsch) and I'm looking to add a center channel and two additional speakers to complete a surround sound system. I want to stick with Klipsch equipment but I'm looking to complete the system without spending too much. My question is really what to add to the bookshelf speakers I already have. Do I need to move them to the rear and get two main or can I keep the two as main and get two rear (either two more bookshelf or something else?). I don't need anything fancy, just looking to make watching movies at home a better experience. Any advice would be much appreciated.