Email to t-mobile phone

[#1]

Totally new to phone email, I need some pretty basic advice in layman's terms.
T-mobile say to receive emails on my phone I need to send them (online) the email address and password and they'll send the set-up to my phone automatically.
Sounds pretty easy - I'll set up a new PN email address specifically for this.
But is there anything I need to know?
There's a sense of dubiousness hanging over this... I can't even find out exactly what they're going to charge me for sent/received emails. It's all about as clear as mud at the moment.
This isn't a smartphone exactly (T-mobile Vairy Touch II), but does do internet and email.
ian

[#2]

If they are only asking for e-mail address and password then I doubt it will work with PlusNet e-mail. As username+mailbox is required for access.

[#3]

actually.....
Wow, that was easy!
Yep, it did go. Took about 20 seconds!!  Just username, password, and select PlusNet from the drop-down.
And it was only 11p to receive a couple of emails. I thought it might be about 30p a go (on PAYG).
Now the only problem is that PN send out emails and mailshots to all your addresses at once, including the non-PN address.
Is there a way to get PN to only send to one?!
(So's we don't have to pay for unwanted ones on the phone? And delete repeated stuff from all other accounts, come to that.)