As you wrote in the comment your are mainly looking for performance testing and functional testing,
For performance testing I would recommend you user Jmeter. It is a java based tool so it should work really fine and for web applications I would suggest you record your test scripts using Blazemeter (an extension of Google Chrome). Here is a tutorial to help you with it - http://testacy.co.in/performance-testing-jmeter/
For functional testing I would suggest you to use Selenium Webdriver and if you are familiar with the TestNG framework of Webdriver that would be more preferable. Since Selenium is open source project you will get a lot of help from countless blogs and forums dedicated to it.
Regards,
Milin Patel
Software Tester