[newaccount74]

The website needs to include VAT in the price if they sell to consumers, and can show prices without VAT if they sell only to businesses. VAT depends only on country, so that is not as difficult to calculate as sales tax in the US.

Some companies (eg. Alternate) have different websites for consumers and business customers, other companies (eg. Conrad) allow you to toggle between pricing modes (with tax or without).

The price is usually shown without shipping, but there's usually a little button "calculate shipping prices" where you can type your zip code and then they show the shipping prices.