How about:

"Roll On, Saskatchewan" by Stompin' Tom Conners.
"Field Behind The Plough" by Stan Rogers.

I don't have my Diamond Joe White CD with me (entitled "Honestly", and I highly recommend it -- former cowboy,"real" cowboy -- now in his day job he runs Diamond Joe's Plumbing) and he writes almost exclusively about the Canadian west. I suspect Ian Tyson might have something appropriate too.

The three CD collection "A Folksong Portrait -- Canada" Mercury/Polygram 769748000-2, originally on Smithsonian Folkways, has these Prairie songs:

The Northern Trappers Rendezvous
The Little Old Sod Shanty
O Bury Me Not On the Lone Prairie
Barbara Allen [it claims this is a Saskatchewan version of it, I kid you not, that heart-breaking girl gets around]
Johnny Sands
Chanson de Riel [also claims this is from Saskatchewan, although IIRC Riel was busiest in Manitoba; if he counts then Diamond Joe does a great song about him on the aforementioned CD]
Funky Jim [????, so it says, also from Saskatchewan]
A Poor Little Girl In Saskatchewan
Saskatchewan

Please note that this CD is mainly field recording stuff, and therefore for the hard core folkies only. No lovers of slick production need apply. (However, a younger Wade Helmsworth sings The Blackfly Song under the Ontario section, and under the Atlantic section it has the version of False Knight On The Road sung to The Flowers of Edinborough.) There are also some native songs from Saskatchewan, if you are up to it.