As answered in an earlier post you probably won't see much of them now untill the spring when the weather starts to warm up. As to feeding them, if (as it sounds) you have inherited a established pond it's amazing how much natural food is in the system, the pellets etc we feed them actually only promote growth, enhance their colours and help keep them healthy. As I was told when I first set up my pond feed them little and often and that if there is any left after about 5mins you've given them to much, a bit trial and error but you soon get there. If you have got a pump and filter system I run mine for a couple of hours a day through the winter to circulate the water and keep the bacteria in the filter active, but you shouldn't have any problems till summer