<p>First, get yourself a good textbook...probably the one your school uses would be a good choice. I just did a quick google search and came up with <a href="http://www.geocities.com/CapeCanaveral/Launchpad/2426/%5B/url%5D">http://www.geocities.com/CapeCanaveral/Launchpad/2426/</a> there are other links at <a href="http://mathforum.org/library/topics/precalc/%5B/url%5D">http://mathforum.org/library/topics/precalc/</a></p>
<p>I didn't poke around much, but the first one looks fairly complete.</p>