I remember reading a children's book several years ago about a young girl and her family on the Oregon trail. From what I remember, it was a fiction series and she goes through a lot of adventures on her way there. She makes friends with a young boy, I believe run into a situation with a river crossing, and when they get to their new home, there was a time where they had trouble due to the gold rush. I'm really not sure but I hope someone can help me!

How about The Dear America series -- Across the Wide and Lonesome Prairie by Kristiana Gregory.

http://www.amazon.com/Across-Wide-Lonesome-Prairie-Campbell/dp/0590226517

Ask at the children's reference desk -- reader's advisory. They will check print material and databases to find what you are looking for.

How about the Retta Barre's Oregon Trail series by Stephen A. Bly?