My rat Shiver died a few months ago and now my other Nibbles has just recently died. 

I was just wondering if there are and good rat breeders in Minnesota.

(perferrably close to minnetonka)

There are no good breeders in MN that I know of.
However, there are tons and tons of needy rats right here who need help!
I'm in the TC area, but if you look at Petfinder.com, there are always rats in our local humane societies.
Eddie and Jake, the smeezers in my sig, are from the Hudson Rd. Humane Society.
We also have Whipstaff Rescue in Solway (bit of a trek) and there always seem to be rats in need on our local branch of craigslist.
Shaz over at Rhinelander in WI will transport, if her rescue is back up and running, and I've even had Kaia at HVRR in Michigan fly rats to me before.

Honestly, there is no reason to resort to buying a rat in this part of MN.
So many rescues need homes.

Oh goodness,
lookit this little one in Burnsville HS... my heart...can't...take..cuteness....
http://www.petfinder.com/petnote/displaypet.cgi?petid=11958416

The AHS only has a few kiddos listed, but I know there are usually more who aren't online yet.
My boys are just dolls and my former HS kid, Mattie, lived to 30 months with no health issues, friendly as can be.
I really like our Humane Societies.

I'm in MN as well and I don't know of any breeders here but definetely check out the humane societys. The coon rapids humane society has a few very sweet girls right now(I was just there visiting them earlier). Betty is a sweetheart if you want to take in a single rat and find her a friend. Someone adopted her cagemate but not her... Betsy and Julie are very sweet and curious but a bit skittish so they need some more socializing. I didn't get a chance to look at the single boy in woodbury because he was just getting over a uri the last time I was there and I was bringing home a pair so didn't want to expose them! The pair of boys in Buffalo(Krona and Peseta) are adorable but very undersocialized. They need a bit of work. One was rather nippy and the other was skittish but cuddling with me by the time I left. I don't work there but spend way too much time visiting the ratties and bringing them toys and hammocks so probably way more info then you needed to know but these babies need homes! =p