Mac Mail problems

I just switched from Eudora to Mac Mail. Having some problems. Where is it possible to select several emails and send them all at once, rather than sending each one separately? I have 3 separate folders for 3 different email addresses. The first additional address mail goes to its own folder as well as the main IN folder, but the second address doesn't. How do I get it to go there? Lastly, the Mail site's "Email a Web Link Instantly" procedure doesn't work. When going to Services in menu, then to Mail it goes to Send Selection, but that is greyed out, so it doesn't create a new email with the link in it.