Inventory DB and Paypal IPN

[kappatango]

Hi,

I have created a site for my wife as she is just embarking on the wide world of Internet sales.

I have integrated the free Paypal Cart buttons one one test page (http://enes.dnsalias.com/BEW/index.php?location=testpay) and payment can progress to delivery. At the moment this is just one page available on my website staging environment, though Paypal is live.

Here's the question's,:

I want to have a simple inventory MySQL table. I am pretty sure, with the low volumes we will encounter, that a single PRODUCTS table will suffice. This would consist of:

Product Code (PK)
Product Name
Available Colours
Product Retail Cost
Quantity Available

1: How to display the Availability on the product page?
2: How to disable the buy button if a product/Colour is out of Stock?
3: Will Paypal IPN be easy to integrate for stock levels Update? (or is there a simpler Direct Dynamic way?? )

I don't necessarily want code, just some pointers on how to create the link between Dynamic Page and DB table.... I use Dreamweaver CS3.

Thanks in advance, I hope I have been clear :)

Karl