[Dixielandjazz] iMac and MP3

[Bill Haesler]

Dear friends,
****Unless you have a Mac, please delete now.*****

I have just downloaded a CD track into my iTunes playlist and want to 
send to a musician mate for research purposes.
Now, how do I sent it as an email attachment?
I can't find anything in my iMac 'help' books on how to forward it, 
other than burning to a disc and snail-mailing it!
There has to be another way, as people send me MP3s all the time.
Kind regards,
Bill.