stay away from the "ebay" brands and you will be OK. Expect to spend $350-500 for some decent-good name brand stuff, less if you come across a good deal.
You could do complete coilovers, or buy new aftermarket struts and new lowering springs separately. Putting lowering springs on your oem struts will kill them quickly and then the ride quality will be bad and bouncy like a hoopty. Since you won't be going too low, there's no need for a camber kit. Just get an alignment after everything is installed and the springs have had a couple of days to settle.
You'll love how well civics handle after they're lowered. After that you'll probably want some wider 15" wheels/tires to take full advantage of the cornering capabilities. All the above will help the looks of your car too so you're knocking out the looks and handling with one punch
