Siddhartha is a story about discovering ones' purpose in life, suggesting that an individuals' political,social, or economic status does not guarantee inner peace or spiritual fulfillment. Siddhartha is a novel that takes the reader through his quest for inner peace and purpose. Herman Hess connects the reader with Siddhartha by describing the humanity of Siddhartha's emotions. For example, Siddhartha's self denial of truth and untamed sexual desire cloud his ability to find purpose. However, after his trials and tribulations he finds peace upon the river. Ironically Herman Hess seems to infuse Transcendentalism, a literary movement steeped in the belief that humanity must turn back to nature in order to redefine their purpose. For it is upon a river that Siddhartha finally begins to feel the purpose of his life.
Enotes has several references that will help you in your research. Although a novel, be sure to look at both the literary and historical references of Transcendentalism and Buddhism. Both will be of great help to your project.
I think that the previous posts are extremely strong in their suggestions. I might want to add one more element. There is nothing like being able to talk about the challenges in reading the book. Whether this discussion is online, through posting responses back and forth, or talking to other students/ colleagues who are enduring the same challenges in reading, the dialectical format approach to reading literature can be very empowering. It enhances understanding of the book because you are talking about it and exploring it with the viewpoints of one or more people. The other thing it does is that it breaks down the "boogey man" aspect of learning. When students confront challenging situations in their school work, their natural tendency is to internalize it and struggle independently. Struggle is good and very important to learning, but it is important to see the community element to learning enhanced by talking out academic challenges. I think you will find that in approaching other people in your class, in particular, about challenges in reading the book, your own challenges might subside a bit.
You might also look into a basic explanation of Buddhism and the path to enlightenment. Check out the link below for background information.
When you read, be sure to write down any questions you have about the book and material. You can then ask those questions in class or post them here.
Good Luck, and happy reading!
Check out the summary and analysis at http://www.enotes.com/siddhartha
if you are having trouble. Try reading it slowly and paraphrasing rather than trying to understand too much at once.