Just found this site called the Virtual University Gazette which has rankings of 25 of the best regionally accredited online MBA programs. Here is the list of the first 10 ...

1. East Carolina University (NC) $3,578 (NC); $13,212 (Others)
2. West Texas A&M (TX) $3,730 (TX); $11,696 (Others)
3. Chadron State University (NE) $3,960 (NE); $7,920 (Others)
4. University of Huston Victoria (TX) $6,360 (TX); $12,618 (Others)
5. Amberton University (TX) $7,200
6. Stephens College (MO) $8,760
7. Morehead State University (KY) $8,820 (KY); $18,960 (Others)
8. California State University DH (CA) $9,000
9. Park University (MO) $9,720
10. Liberty University (VA) $10,260

They also have rankings of the 25 best AACSB-accredited online MBAs. Here are the first ten of those ...

1. Cameron University (OK) $2,760 (OK); $6,357 (Others)
2. Western Illinois University (IL) $4,744 (IL); $9,487 (Others)
3. Ball State University (IN) $5,500 (IN); $9,700 (Others)
4. Florida Atlantic University (FL) $6,886 (FL); $23,172 (Others)
5. University of North Dakota (ND) $6,956
6. University of Nebraska (NE) $7,680 (NE); $19,080 (Others)
7. East Tennessee State University (TN) $8,931 (TN); $22,347 (Others)
8. University of arkansas (AR) $9,612 (AR); $19,308 (Others)
9. University of Texas System (TX) $10,240
10. University System of Georgia (GA) $10,500

Virtual Gazette also has complete profiles of 178 graduate schools, which is a nice resource. Go here to access that part of the site.