I'm not super into Okami's OST, but here is the field theme, and it's a lot better than I remember it. http://www.youtube.com/watch?v=wif3MEdRaPA&feature=related
Here is my favorite Zelda field theme (Twilight Princess, Hyrule Field): http://www.youtube.com/watch?v=AyjBrU0orfE
Here is another great Zelda field theme (and yes, this does count): http://www.youtube.com/watch?v=gN_x1rpGbY8
I feel like game makers do this on purpose. They put nothing but respawning enemies and the best damn music and leave you to it. --- NDF Assemble: Heroes of Ruin(3DS): July 17, Paper Mario Sticker Star(3DS): Holiday, Professor Layton and the Miracle Mask(3DS):November.
So many aspects of game design are to get you to come back. Music is a big part of it, but more importantly, the game design hooks you in. That's one of the reasons I love indie/arcade style games, because of how very easy they are to put down.