Validation help!

Can someone please help me with this JavaScript. I have some of the validation done, but I don't know how to finish it.
I have the following code:

Please ignore all of the div classes. I'm using those to format it later. Anyways, when someone presses the submit button, I need to validate that none of the following are left blank:
name, address, state, zipcode, phone number, email address.
I also need to validate that the email address is 5 or more characters long, the email has a period in it, there is at least 3 letters after the period, that a book has been selected from the "select the book" drop down menu, and the Qty is at least 1. I need everything to pop up in one box. Also, if everything is filled out correctly, I need to display a message confirming the book selection and the number of books.

Source: http://community.livejournal.com/javascript/157708.html

Internet Books
Programming Languages
Networking Books
Networking Books
Networking Books
Networking Books