You can show them shipping charges as soon as you know their address. If you have people log in, then you can use the stored profile information to calculate shipping charges on the cart page instead of waiting for the checkout pages.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.