I love to read pioneer stories, and this is my favorite so far:
Amazon.com: One Woman's West: Recollections of the Oregon Trail and Settling of the Northwest Country: Books: Martha Gay Masterson
It's a woman's journal of travelling to Oregon on the trail, and then growing up in the Willamette Valley. It's most interesting because so many of the places she lived are very familiar to me, and some seem to not exist at all anymore. I would love to retrace her steps and see where she lived.
I think retracing the trail would be fascinating, but to be authentic you have to walk it just like they did!