Where? Usually right out my front door and I get mauled and stepped on by my dogs. Most of my weekly runs are some variation around my farm. It is a mix of soft dirt with rocks and debris, gravel, a couple sections nice packed dirt, and if I run in the field, crop stubble. If I need more distance and my soles are a little sore, I repeat on the smoother sections. Confused dog looks I tell ya. It all changes with colder weather and moisture though. Longer runs off the farm are tough. Nasty graveled roads or old country chip seal. I stay off the highway because of no shoulder and large vehicles. I have toyed with the idea of running on it in the middle of the night, it is a nice medium chip seal. When we head to town I make sure to bring my running gear for a longer run on smoother pavement. It's like butter, I just have to be careful not to push the pace and revert back to my old habits. My wife does the shopping and I get to run. Also, many trail running options with not too far of a drive.
How often? I can finally run every day and I really enjoy that. I don't really have a schedule, because a long run, hike, or race will usually affect the weekly runs. I'm pretty stubborn and run on sore soles. Joint or foot pain, I'm a little more cautious. If it is just sore muscles, I have found a short, easy run or walk is the best remedy. My work slows down during the winter, so I am trying to get in as much as I can.