There are various kinds of lodging available including hotels, ryokans, minshukus, guesthouses, B&Bs, and more. Some useful resources in figuring out where to stay are the Map Books and DATA BOOKs, Google maps, websites made by thru-hikers, and tourist association pamphlets and websites.

General incorporated association Tancko Canary “みちのく潮風トレイル宿泊リスト” (Michinoku Coastal Trail lodging list)
https://tanckocanary.com/archives/news/1082/

MICHINOKU COASTAL TRAIL “Accommodation” : https://www.michinokutrail.com/accommodation

For information on discount plans for hikers, spots that offer places for MCT hikers to camp as a special favor, and more, see MCT maps made by local governments, etc. and the Trail Supporters webpage.

Trail Supporters : https://mct-a.org/en/hike/supporters/

Local Maps : https://mct-a.org/blog-category/local-activities/

You can also get good information about lodging from social media groups.

Facebook 「みちのく潮風トレイルハイカーズコミュニティ」(“Michinoku Coastal Trail Hiker’s Community”)
https://www.facebook.com/groups/2074391539536922

Facebook “Michinoku Coastal Trail” : https://www.facebook.com/groups/michinokucoastaltrail

If you can’t find any place to stay in the direction you plan to hike, you can try using public transportation or shuttle services offered by your hotel to get back to your lodging at night until you reach a point where there are places to stay again.