hi felzdown you might want to refer to the thread "questions about vpost" in the parenting general discusson section. that's for the delivery of the items part.
i've bought from amazon quite a few times. just create an account and you can start buying. but when you buy electrical items, gotta note that US plugs is different from SG. you'll need an adapter to be able to use those items in SG.
things from amazon is actually quite expensive but if you want convenience you can buy from there. my hubby's cousin introduced a site called simonsays but i've not used it before. the site compares prices for you between US online stores.