Hi, yeah, this is a mess to have to deal with. It is horrible when you do something accidently and it just causes such headaches.
There are a couple of things you can do to start the process of ending this sort of email. First, click the "Spam" or "This is spam" button on each unwanted and/or offensive email you receive.
This will begin training the email anti-spam program to know what you consider spam and what is viable email. This is how the email anti-spam tool determines whether or not to send an email to your inbox, or to the "Bulk Mail" box, which is where all known or suspected spam lands.
Now, you need to be sure your Spam Tool is activated. Click on Options-Mail Options-then Click on the Spam link to the left of the screen, then under "Spamguard" (If in Yahoo! Mail) make sure a check mark is in front of "automatically send Spam to my Spam folder".
Now that your Spamguard is activated the tool will begin to place suspected spam in the Spam folder or Bulk Folder in other email programs. If you are using a different email account than Yahoo! Mail, these too have there own Spam Tools, just go into that accounts options, and follow the links for Spam and make sure it is enabled. Most mail programs have simular tools to handle Spam.
You also need to know that due to how each person is different, what you consider Spam another considers viable Mail, so the tool has to "learn" which is which for each individual account. This happens by your clicking, "Spam" or "This is Spam" or whichever button your email account uses to "Report as Spam". As you report email messages that land in your inbox as Spam the tool will begin to sort these out automatically.
Make sure you check your Spam or Bulk folder every so often as viable mail may wind up in this folder while the tool is learning your habits. All you need to do is check, "This is Not Spam" and you continue to train your Spamguard Tool what you consider spam. It can take up to three months for this to occur, so please be patient.
OK, while you are in the Spam section of the Mail Options, look down the the list of items. You will find a section which allows you to block individual email addresses. Use thiss to block the most offensive emails. This will stop them from hitting your inbox, and in fact will bounce back to the sender with an undeliverable note which will make them think that your account is not active any longer.
Now, only do this on the most offensive, or if you just can't stand to wait for the Spamguard tool to do its job. Because by blocking these addresses you are preventing the Spamguard tool learning what is Spam. It is great for the most offensive, or if you have an individual who is harrassing or otherwise making a fool of themselves.
Please be patient while these tools go to work for you. Also, if you wish to stop Spam it is a good idea to read the Privacy Policy of any websites you give your email address to. Many websites sell or give away your addresses to others who then begin sending all sorts of unswanted mail. Read the policy carefully, because some will report that while they don't sell or rent your information, they give it to third party partners whom they have no control over and whom may have Privacy Policies different from the original website. Once you give your address out to those who sell or rent it you will become unendated with Spam.
Also, Yahoo! Mail Plus has a feature which I use extensively in registering at websites. I find the $19.99 yearly fee well worth these features. First it has SpamGuard Plus, which is stronger and smarter than the basic Spamguard tool.
Secondly, Yahoo! Mail Plus has what are called Disposable Addressess. These addresses can be created quickly and accessed easily. They are super for signing up at sites and if a particular address begins to receive Spam all you have to do is delete it and no more Spam from that source! I love using disposable addresses and find it very useful in stopping Spam. To create disposable addresses you provide a first section of the disposible addresses which will be on all of them. They all end with "yahoo.com", and when you create one you add certain charactores in the middle. For example, the main section can be "butterfly", the end is "yahoo.com", then you add "-hsw", and you end up with a disposable address for the website HowStuffWorks which looks like this: butterfly-hsw(at)yahoo.com. For me I always use initials of the site to help me identify which disposible address is for which website. Now, the word "butterfly" is always in every single disposible address and is only an example of how these work. When you go to create a new disposible address you simply add the "-x", with "x" being any set of allowed charachtors. As a guy I am sure you would prefer a more guy sounding static section for all your disposible addresses if you should decide this is a feature worth upgrading your Yahoo! Mail acount to Yahoo! Mail Plus. It is well worth it for me. There are other features of the Plus account too, one of which is no ads in your account. The only part of Yahoo! Mail Plus that news or ads may appear are in the Home section, but you can set a preference to open your mail account at your Inbox, thus bypassing the Home tab all together, and never see those items. That is what I do.
Good luck in fighting off this horrid Spam you are currently receiving and have a great day.