Buying stamps while in different prefectures

If I want to mail postcards from different prefectures while in Japan does each prefecture sell different stamps in their post offices? I'm hoping to get a variety of stamps. Thank you.

There are prefecture-themed stamps, but many are available nationwide - for example, I can buy stamps depicting Hokkaido in a post office in Tokyo.

There are some postcards sold by post offices that are only available from post offices in that area/prefecture, though.

http://www.postacollect.com/gotochi/

you can get local 'Keshiin (postmark)' at the postoffice, the date you get stamped on the postal stamp. Go in the post office and ask for '記念印（kinen-inn)’or ’風景印(fuukei-inn)’at the desk instead of putting your letter in the postbox.