Erm, the rounded edge thing is usually a picutre mate. Therefore you do all the work for it in photoshop or something of the like and then save it as a jpeg/gif and then load in the image in an element such asa <div></div>
Check
here for an example. BUT DO NOT use tables like this guy does, instead use your imagination and convert it to <div></div>'s!
HTH's.
Boog's.