I have a 10 inch square solo-baric kicker subwoofer it came with a 350 watt kicker amp. Im looking at getting new mid sound speakers, for starters is my 350 watt amp putting out enough energy for my subwoofer, and if i want to run my new mids (5.25 round) into my amp what size amp will i need, or can i put them into my current amp. thanks

Not sure about the sub power and amp. I'd say that should be plenty. No, you'll need a new amp for the mids/highs. Look for something a hair bigger than what the speakers are rated at. Use the RMS rating and not the PEAK power for your decision.