spammers hijacked email address/url

1) You can't. Email is inherently insecure. I could email you right now from [email protected] without any special software. You can however stop the bounce backs by turning off your catchall (wildcard) email alias and only receive emails to the specific addresses you actually use.

2) I doubt you could catch them. Most spammers that use these kind of tactics spread their junk via thousands of remote zombie machines (computers infected with trojans).

In my job I have to deal with this question on a daily basis. It's a sad fact, but email is just not a good enough solution for our electronic mail needs any longer. We need a better solution and old school email needs to be stopped - it'll be a huge transition but it would be worth it for a world without spam!