Francine, "Mail"
is free, it comes with every version of OS X, it is upgraded
free via Software Update or by going to Apple's Downloads area. "Mail" is simply a program that will allow you to access any and every email account you might ever have or want, no matter who it is with. And, of course, it will allow you to send emails to anyone for whom you have an address. The advantage of "Mail" over any other program, is that it 'knows' about Address Book and iCal (both also free from Apple) and can communicate with them to keep all the same information in each one up-to-date, without having to copy/paste. All other email programs, even web-based allow you to have an 'address book' and maybe even a calendar, and some of them may even 'talk' to one another, but they are either clunky, pay to use or don't keep the info on your own drive. Entourage for Mac does all that, also, I guess. So if you want to keep using MS apps, that should work for you. It is not free, of course.
But no matter how you get or read your email, you will have to be paying someone, somehow. It may be only by letting them read every thing you send or receive as with GMail or Yahoo (ads?!). But you surely have an email account with whoever gives you access to the Internet. I've never heard of an Internet Service Provider (ISP) having a plan that did
not include at least one email account. Perhaps there is one, however. But whoever your ISP is will be charging you a certain amount each month. Part of what you are paying for is a certain amount of
email storage space and most of the rest is simply for connecting you to the Internet.
That is where the cost comes in, accessing the Internet,
not the Apple program called "Mail." It is unfortunate, IMHO, that it even has that name. It is confusing to use a word that has an already established, widespread use for any application or program. OTOH, I'm not sure what "Outlook" even with "Express" added has to do with email. Nor does "Entourage" have any connotations, for me anyway, of any kind of communicating, much less emailing.
So, finally, one question remains unanswered: Who is your ISP? Who do you pay regularly for your access to the Internet?