When you start out in the freelance world one of the hardest question to answer is how to do you charge. You don’t want to charge too much that you won’t be able to get work but you don’t want to charge too little either. You have to determine what your time is worth to you and what type of client of you want.
Carrie Dils wrote a post, What’s it Worth to You?, about this very subject. If this is something you struggle with go read the article and don’t forget to check out the comments, they are just as good as the article.