How do I send an email to numerous people, so that one recipient can't see the other peoples adresses?

Do a blind copy. Then it just comes up “undisclosed recipients”.

Send it to youself and include everybody else in the bcc box

@jbfletcherfan JINX :-)

In Os Leopard’s address book, there is a way to start a group folder; you can send it zipped. But dragging 800 names into it? Yoicks.

Use the BCC field, but be careful not to confuse the two :)

CC stands for Carbon Copy. A copy of the email is sent to any address that appear in this field. CC addresses are included in the message header of the email and thus visible to all recipients of the message. Hence, it is functionally identical to the ‘To:’ field.

BCC stands for Blind Carbon Copy. A copy of the email is also sent to any address that appears in this field, but those addresses do not appear in the message header of the sent email. Hence, recipients of the ‘To’ and ‘CC’ fields will not know that a copy of the message was sent to the recipients in the BCC field.

(source)

@gailcalled I echo that!

With 800 addresses, I hope you have a comfortable chair.

@jbfletcherfan: And elastic wrist supports.

@gailcalled And a glass of wine for energy. . . :D

Your email client may not support the ability to load that many clients onto BCC; you may want to organize groups of recipients as @gailcalled and others indicated; then send the email out as several emails, with one group per email (say, 100–150 per group). Just remember to always drop the groups into the BCC field!

@jbfletcherfan well the worst thing is, that i have to write all the email addresses onto the computer from small pieces of paper. Tedious work, you might say.
@markyy thanks for the answer, great to finally know what those letters stand for!

creat a Gmail account and enter your email addresses in the addressbook. Once they are entered, you can Compose an email, click on BCC, then choose the “ALL” option to include everyone in the mailing. . . . hit SEND and you’re done.

Just make sure that you’re not spamming people.

Depending on what Mail client you are using, you may have to do this only once.
Create a custom Distribution List and add the Contact entries to it.

If you have already entered them (even as a BCC), go to your sent items.
Open that item
copy all the entries from the BCC field.
Paste the entries into a new email in the BCC again.
Paste the entries into a custom distribution list if you can.