some strange sounds

I have a 2002 Jeep Wrangler (Sahara) auto-transmission. Recently, some strange sounds have started coming from the Jeep and are now constant. First, a "ticking" sound when the car is moving slowly or quickly. I originally thought there was a pebble or something stuck in a tire, but listening more closely it defeinitely is coming from the car and it is mechanical. Second, is what feels like a joint under my car making a crunching sound when I sometimes come to a stop or when moving slowly in rush-hour. Any advice out there would be most appreciated. Thanks!