I have to say (although I am biased) that I find eNotes to be one of the most helpful web sites I could possibly recommend to any student. The information available through this site is astonishingly comprehensive, and it would certainly be worth subscribing to if you can possibly afford it. The suggestion above -- that you and several friends go in together to buy a subscription -- is a very good one. Or perhaps you could ask your parents to help you buy a subscription. You may also want to check and see if your school can subscribe; I would certainly alert my teachers and the school librarian to the existence of the site.
I have to re-emphasize the advice to read through the questions in the Q&A section. There is more than enough information posted in the Q&A for high-frequency texts to get a pretty good and well rounded picture of a text, inside and out.
After posing a couple of keywords in the search box [such as "Hamlet themes"] rather than going straight to the study guide pages (which are listed first), scroll down to the "Pages Found" links. This will more than likely take you to an answered question in the Q&A. From here, you can use the tabs at the top of the page to see all other Q&A questions for the text you are studying.
I also highly encourage you to see if someone has already asked your question (or something similar) posing it as a new question. Duplicate questions are posed multiple times a day, and are likely going unanswered because they are duplicates.
You might consider going in with several friends and splitting the cost if it is too much for just you to pay. With today's economy the way it is and so many people being unemployed, it makes sense to think smart and share the cost.
In addition to number 3's response, you don't have to pay separately for each web site. You can get a subscription that allows you to see all of the content. In the long run, it's cheaper than paying for each individual study guide.
The way for free-use students etc to view more than the Introduction of Study Guides, is to (1) read an answer to a question posted in the topic and click the eNotes links provided (if provided); (2) post a question in the topic, read your answer and click the eNotes links provided. You might specifically request in the Additional Information box of your question that eNotes links please be provided. Make sense?