Compromised E-mail address ? What action to take?

[#1]

I have had a couple of "weird" messages, purporting to originate from a couple of my contacts, who I do not email very often. 
I am thinking, either their email addresses have been compromised, or mine (is) has....
Can I change my main email address, and retain the old one, so that I can personally "Filter" incoming messages, and instead of responding with my original email address, respond to them with my new email address.. i.e... when the bank emails me, or other "legitimate" emails arrive, I can respond with my new address, and ignore these "spam"/ "virus" type emails
I don`t have a record of everyone who has my email address, so it would take some time to change everyone over to the new one this way,..... but... it would mean I did not "lose" or "miss" an important contact address....

[#2]

You can change your email address easily. If you use the PN system, make sure you have a new user added to the email as the new email you want to use.
I use Gmail and have a dozen or so emails that all are aliases to my main account, I then filter on the user and put it in to separate folders.
Doesn't really make much difference as eventually the spammers will find you. But I would think it is more likely that it is their accounts that are compromised as the email was TO you not from you.

[#3]

OK Thanks HB... a star, as always ! .
Yeah... Unfortunately... I did respond to the first one, saying that I don`t click on suspicious links... so maybe that went back to the spammer, hence the reason I got a second one from another rarely used contact... and because I had two from different rarely used contacts, I am suspecting that MY email address ( address book? ) has been "got at"...

[#4]

Run some malware scanners, etc.
Even changing your email address will not cure it if you are compromised by malware.

[#5]

OK.. Thanks. 

[#6]

Have run Malwarebytes... and it found several PUP`s mainly to do with browser toolbars... and they have been dealt with...
Have talked to one of the guys who "supposedly" sent me one dodgy email... claims he did not send it.. BUT he did open a similar one from the other guy ( which I also received).. and he said that it was for a miracle drug to make you lose 6 stone in 3 weeks or something... and possibly that linky has done the dirty and spammed his email address book...
Have not had any more, same, or similar, so am assuming that I am in the clear....
Thanks for help...