Kate Wendleton of "Through The Brick Wall" fame suggests the "Seven Stories" method.
1) Keep a list going for aws long as it takes of accomplishments in your life which have given you the most pleasure or of which you are proud.
2) When you have 25 (this can take a week or two), choose the 7 which are most important to you.
3)Write a story about each explaining exactly what happened, what you did, how you did it and why you are proud of the accomplishment.
4) Have one or two people you respect read the stories (better not to make it friends but people who don't really know you personally hence no pre-conceived ideas)and ask them to comment on the person who wrote the stories, his strong points, weak points, expected profession.

Note: The accomplishment can be ANYTHING. Could be learning to ride a bike as a child or saving a neighbor from a burning building or setting up your VCR. Anything. Kate recommends that everyone do this periodically as people grow and change and outgrow jobs. Done well, this will give you a very good idea of where you will be happiest.
Good luck. And enjoy the process. Changing jobs is exciting and fulfilling as well as traumatic.