I've used myfitnesspal.com for about a year and a half....well almost 2 years. You log in exercise by time. Type in a type of exercise and several options will list, choose one, and log your time. You can also log your food, and your goals (lose weight, maintain, etc.) It's been a great help to me!

There is a walking program called 10,000 steps a day. Their calculator says that there are approximately 2000 steps per mile (this is based on the average stride length and stride rate of a person). So if you've walked 2000 steps, that equals roughly one mile. 3000 steps = 1.5 miles and so on. Hope this helps!