You can create a Google form and simply embed it in your page with the <iframe> tag. To do this, after creating the form on Google Docs, click on File | Embed and then copy the provided HTML. Paste it on your page. That's it. Below is a simple form we created.
The form above is embedded with the <iframe> tag and it will show in the same way that we created it on Google forms. However, it is possible to change its appearance if we so wish. To do that, instead of using <iframe> to embed the form, we look at its source code (when we go to the Live Form) and copy its HTML and CSS. The form below is the same one, but with some modifications to the CSS and HTML.
We also have done some jQuery/Javascript hacking to get the form to not redirect us to the Google Form thank you page, but instead to show a message on our page.