I'm creating a website with VSD. Only the introduction page, privacy policy, terms and conditions and application page will be accessed by the general public and the rest will be accessed by members of the website only with username and password protection. I'm selling only one thing and that is membership to the website. I need to create a membership application form that will ask the usual questions such as name, address, professional credentials, email, etc and they will press a button that will lead them directly to a Paypal link page (I don't necessarilly need that to happen on my webpage). I definitely need the membership information they submit linked to the payment information...how do I do this? I'm guessing I really don't need a shopping cart since I'm selling only one thing.
I've already got VSD, HTML editor, Forms Creator, and Website Access Manager.

If you have Web Form Builder then you should be good... They just updated it with the payment option. So check it out and it should work perfectly for what you need it for.

Forms Creator?
Form Builder Classic or Web Form Builder 2.0?