<p>this site:
<a href="http://www.mhhe.com/math/precalc/barnettpc5/student_index.mhtml%5B/url%5D">http://www.mhhe.com/math/precalc/barnettpc5/student_index.mhtml</a>
has the entire text of Precalculus 5/e Barnett book.</p>
<p>It's on McGraw-Hill's website. Read around there, should have some practice problems too.</p>