Our Resources pages include:

• Articles. The ones most relevant for you are How to Write a Solution and Learning Through Teaching.
• Books. You'll want to check out those in the For the Pros section.
• Contests. You can hone your solutions writing skills with the USAMTS, the Tournament of Towns, or the MathLinks Contest. Other contests for top students include the Mandelbrot and ARML. Of course, the American Mathematics Competitions provide US students their path to the IMO. Those of you who like doing research projects should get involved with the Siemens Westinghouse Competition.
• Summer Programs. Most of the programs listed on this page are for high school students.
• Links to sites with practice problems. The first site on this list has more Olympiad problems than you'll need for practice!
• Links to other interesting Websites.
• Scholarship Guide for students interested in studying math or other applied problem solving fields at the university level.

Since you're at the Olympiad level, you're probably going to be writing math papers at some point. Check out our LaTeX pages to learn how to typeset them like a pro.