Hakodate or Sapporo to Tokyo

Hi,

Me and my husband would be visiting Japan around May next year. We choose Sapporo Int Airport as our gate of arrival and will arrive there around 8 AM, we plan to spent a day to have a quick culinary tour around Sapporo and Hakodate and take a bullet train or over night train to go to Tokyo at the same day. Is there any web or else where I can find a schedule for each train and at what time the latest train of the day will depart from hakodate to tokyo? How long this trip will take time?

Need advise, thank you in advance