There are a few papers I know of that could be helpful to you:
Tryon, W. W. (2001). Evaluating statistical difference, equivalence, and indeterminacy using inferential confidence intervals: An integrated alternative method of conducting null hypothesis statistical tests. Psychological Methods, 6, 371-386. (FREE PDF)
And a correction:
Tryon, W. W., & Lewis, C. (2008). An Inferential Confidence Interval Method of Establishing Statistical Equivalence That Corrects Tryon’s (2001) Reduction Factor. Psychological Methods, 13, 272-278. (FREE PDF)
Furthermore:
Seaman, M. A. & Serlin, R. C. (1998). Equivalence confidence intervals for two-group comparisons of means. Psychological Methods, Vol 3(4), 403-411.
