Recommendations for a newbie

Well, hello. My name is Sophie and I'm a totally newbie as an e-reader. I'm used to read books, specially because I live far away from where I work and the way there is long, so I have plenty of time to read. Problem is, taking a book with me everywhere it's getting uncomfortable, since I'm reading really long books (for example, I'm reading The Priory of the Orange Tree right now). It's quite heavy and I don't like to have it in the desk because my boss is really strict with any possible distraction (we work at the HR department of a huge company and we often receive visitors). So, I'm thinking about getting a eBook. Any recommendations for a first timer? I don't have a problem with the budget, even though I wouldn't like to spend too much money since I'm just "trying it" right now. Thank you in advance.