Refer to:  http://seleniumcn.cn/read.php?tid=3669&page=1
1. Install firefox
2. Download webdriver for Java: selenium-java-2.29.0.zip
at: http://code.google.com/p/selenium/downloads/list
3. Extract selenium-java-2.29.0.zip to lib of new project in Eclipse.
4. New a class, and paste below code into it:
  
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;
public class Seleniumcn {
public static void main(String args[]) throws Exception {

WebDriver driver = new FirefoxDriver();
driver.get("http://www.baidu.com");
WebElement query = driver.findElement(By.name("wd"));
query.sendKeys("selenium 中文论坛");
WebElement btn = driver.findElement(By.id("su"));
btn.click();
Thread.sleep(5000);
WebElement link = driver.findElement(By
.xpath("//a[@href='http://seleniumcn.cn/']"));
link.click();
Thread.sleep(5000);
driver.switchTo().window(driver.getWindowHandles().toArray(new String[0])[1]);
System.out.println(driver.getTitle());
driver.quit();
}
}

5. Run as-> java application