Analyzing carryover effects

Hey There,
I am a graduate student, currently working on my Master’s thesis. I am attempting to analyze differential carryover effects for a within-subjects design. I have three conditions, counterbalanced of course, and I would like to see how early exposure to one or two conditions affects the other(s). If anyone knows of anything to point me in the correct direction on how to set up and analyze this in SPSS, or any other statistical programs, I would greatly appreciate it. Also, I have been trying to find research that have already analyzed a similar design but have not had any luck there. So if this approach rings any memory bells, then please pass along that info.
Thank you very much for your time.