I spent 10 minutes looking on the interwebs for a list of the church land holdings. Here's what I found:
CA: 13,000 acres of agricultural land, plus an unspecified number of acres of "vacant land"
UT: 5000 acres in Salt Lake County (this number does not include commercial/residential land holdings in Salt Lake City)
Ranch along UT/Wyoming border: 201,000 acres
Washington State: 154,000 acres
IA/IL/MO/IN: 38,540 acres (as of 1991 - there have been some major purchases by the Church in the midwest since then, so this number is low)
Nebraska: 270,000 acres
Florida: 670,000 acres
OK/KS farm/ranch land: 70,000 acres.
I know the church has a lot of holdings in Arizona and Idaho, but I wasn't able to get a good feel for those numbers. I know there's at least 12,000 acres near Twin Falls that is largely potato farms. The Church has bought up a lot of development ground in the Phoenix area as well.
With just the stuff I'm sure of, it's over 1,433,000 acres.