Does anyone know of a way to track how much overall time I've spent on Skyrim? I've deleted games so I can't just add up hours.

Check your save file, it should tell you.

Steam should track your total hours for you. On PS3 you can see the time played by hovering over save files, but if you've deleted characters then you won't be able to add them all up. I'm not sure how you do it on 360.