Help me with my website

hello

I have recently set up a website using dreamweaver cs4 and need some help / tutoring / showing how to carry out the following tasks on my website :

1 ) add a shopping cart, ideally one that is easy to maintain and if possible monitor stock levels -eg, so people cannot order 5 items if i only have 4 in stock.

2 ) make it more presentable (dreamweaver aint too user friendly for beginners!) - im not wanting any flash images just something that looks better than it currently does.

3 ) add a form for visitors to register/send me their contact details, link and store this info in a database that i can access easily. - in view of emailing / or even mailing customers flyers in the post.

4 ) any advise or ideas for me to add to my site