You can contact SE via the "Contact Us" link on the bottom of every page of the website.
Is that the way to go?
I don't think so.
I received spam via my website contact form from somebody who specified that he got my contact via one of the SE sites.
Then you may not want your info on there, regardless.
Needless to say, SE has no control on what the world does with info you publicize, and for your info, your SE profile is most probably public.
I understand that SE may not have to deal this kind of spam, but they may be able to track down the profile of the person who did it.
Wouldn't attempting in tracking down the person be just that? Namely "have to deal with this kind of Spam"?
Who should I contact to report this issue?
Try the Contact us on the bottom, if posting here doesn't solve it.
Disclaimer: I don't think that it's the right thing to do. You wrote yourself that "I understand that SE may not have to deal this kind of".
To make it clear :
It's not a matter of private info being used (my website contact form isn't private!).
Your SE profile is not either.
I'm not complaining about somebody contacting me via my website.
That does seems to be just your complaint.
I just think that if somebody if using SE to spam instead of using SE as it is intended (helping the community), SE should know about it.
Just like they do when somebody if spamming on the forums.
No one seems to be using SE to spam you.
Rather, the info you provided, which was, and is your choice, was used.
SE should know about it, IF it happens on SE.
Here, it's happening from your website.
Again, you can post here, and use (without my agreement, for whatever matter it may matter) the Contact us on the bottom, but my best suggestion is to remove that information, as SE has zero control as long as it is public.
P.S.: How would it help anyhow if they track the person down?