For online e-mail list management, try ListBot (www.listbot.com), Milomail (www.milomail.com) or Yahoo Groups (http://groups."yahoo.com/). These programs are supported by advertising, and this is generally acceptable in hobby areas, but professionals may need to look at some other choices.
If you are into Perl, Unix and other more advanced server options, then Majordomo (www.greatcircle.com/majordomo) is a great choice. It is free and a copy of the program with accompanying FAQ is on the cover CD. Be warned - this is for advanced users only!
Many list manager programs are available, and selecting the right one really depends on your needs. They start at around $US30, but be sure to take the trials for a spin before laying out your money. Two packages to try include EBMailer ($US20, www.viratech.comi) and Dynamic Opt-in Emailer (www.apexpacific."com"), which is a good program but a bit overpriced at $220.
Bonus tip: do not use your personal e-mail address for mailouts; it can cause many problems such as mixing your personal and professional e-mails, and choke your inbox if your list is large, not to mention that the address is likely to end up on spam lists.
Extracting e-mail addresses and duplicate addressesIf your list is small, it can probably be managed by simple subscribe/unsubscribe requests sent from a Web site to your e-mail (see www.response-o-matic.com to add this option to your site). Requests will appear in your inbox with text surrounding the e-mail. You will then need to copy the address manually or use an e-mail extraction tool, such as the aptly named E-mail Extractor (www.geocities.com/eextractor).
To make this a real time-saver, collect all your requests in one folder (use a filter to do this automatically). If you use Outlook Express, you can then quickly combine all the messages and E-mail Extractor will spit out a list of addresses free of duplicates. To create one large text file for the program to process, select all the messages, then from the menu select Message-Combine and Decode. There is no need to sort the e-mail when the option appears. Click OK and a new message window will appear. Convert this to a text file by selecting File-Save As. and choose "Text" as the file type. After processing with E-mail Extractor, you will have a text file containing your e-mail addresses neatly listed.
Bonus tips: this trick of combining messages can be a good way to save a collection of e-mails in one simple document. If you have an e-mail list loaded with duplicates, E-mail Extractor can weed them out with minimal fuss.
There are tools that claim that they can check the validity of e-mail addresses without sending out a message. Unfortunately, thanks to spammers, this technique can result in you being banned as a spammer by some ISPs (your IP address is banned), or just give false results.
The general approach taken by e-mail verifiers is that the program will attempt to connect with an ISP as if it was sending an e-mail. If the connection is rejected, the program shows that the address may be invalid. Some ISPs can detect this type of approach and will treat it as if a spammer is trying to verify their spam list. Other ISPs will display a polite note saying that you should not be trying to send e-mail by this method!
Instead of using these kinds of programs, you are better off buying a list manager that sorts through bounced e-mail requests and automatically deletes the address. However, if you still want to try a program, then the $US40 Advanced Maillist Verify (www.mailutilities.com) is one of the better choices around.