Shopping Cart W/ Google Checkout

OK, this is the second round on this project. The last guy just stopped for no reason at all, and wouldn't contact me, and he was a week overdue from the deadline. Please do not bid if you cannot do this or have no experience in this field. I'd like to integrate my pre-existing website (peluchedesigns(dot)c/o/m). I'd like to keep the design the same, but in the bracelets and earrings pages, I'd like to have a shopping cart that has some features. I'd like it to show the quantity available and a "buy it now." This will have this goto the google checkout. I'd like it to calculate shipping as well. Once the product is bought, I'd like this to subtract the quantity available by one, and if there was one left to say, "sold out." There should be an administration page where you can login and add a bracelet or earring (or whatever else) and manage the inventory. I should be allowed to add categories and add products easily. See the upload screen shots for a better idea of what I'm looking for. It's important that I can edit and add new pages and new products later on, and be easy to integrate again a different webpages, so It needs to be able to be flexible in this way. My host only supports SQL Server 2005, so mysql will not work. My host does, however, support php. The last guy used ASP .NET to program, and it looked good. There are about a million different free shopping cart codes, so the programming of it shouldn't be that big of a deal, but I just can't get this to work because I don't have a lot of experience in this field. NOTE: I am getting tired of having programmers quit in the middle. I have lost a lot of money shuffling money around -> I will not put an escrow payment until I have some hard evidence that you are almost done.