you may need to do some list cleaning , since you can only have 100 on the list (yah-who)  ~ and we all know how popular you are..... 

well most of the time, people will just look at their list. and try the right click  and delete option

but then the realize that they still see the persons name coming and going in the lower left of the screen. and they think, heck  i deleted then from my list!!

OPTION #1

you can go to http://edit.yahoo.com/config/set_buddylist   there you can select the word  edit  next to any friends group to see your buddy list...................... 

BE VERY CAREFUL...DO NOT CLICK DELETE ... there is no confirm delete message there....... all will be lost....

the new link is http://messenger.yahoo.com/edit/add/ and does NOT appear to allow you to remove your id from anothers list. i tested it with my own ids. i still see me ... but you can delete them off your list fine....

OPTION #2

person doesn't show on that edit buddy list?     or want to just remove someone ? no muss no fuss? the old yah-whoooo  nobud link is dead~ apparently it violated their new privacy policies...... still works from here tho...

so, go  log in on your account, (via mail or web browser, then go here  /nobud2.html    

then just enter the id they added you under, their name, and a message...... click adios, loser and they are history! if it wont allow  the delete....  try your other names on the account.

occasionally someone will add you on their main account name, rather than an alias  =o(    and that makes them almost impossible to delete.

the question that is often raised next is.... will they get a notice that i removed them? if you just right-click off messenger ~ nope... if you use the  edit buddy page?  no alert. if you use the nobud link ~ most likely yes they will get an alert....

as as said before, you will only see who you accepted and added to your buddy list. if you just accepted ~ no way to find out who's list you may be on.... that's an old Ichat command and isn't  supported on yahoo.

and its impossible to add they say.... sorry :( ~ but a good idea occurred to me the other day..  just change your status to read something like... " i am clearing my buddy list, message me or i am removing you!" or "see my naked webcam!" ~ i bet you see names message you that you had no idea had buddied you