Shoutbox

Ok well i will try and explain this best i can.
All my cds that i have used to obtain songs to put on my ipod i decided to rip them to mp3 first and place them all in a folder called "Ripped Mp3's" (imaginative i know) and inside that folder is many subfolders of bands and inside those folders is albums.
My problem is in the last few days i have got a fair few cds and placed them each in a folder as per where they belong.
My question is that when adding these new songs to iTunes and using the add folder to library function i can do it fine. however is there an easier way to add my songs instead of remembering every album i got with chance of missing some. for example can i just Add the whole folder "Ripped Mp3's".
I am pretty sure when it does this it adds every single song again as i tried to do a little simple test with a few songs. And as a result of this i end up with like a thousand duplicate songs.
I then came across the Show duplicate files function and thought oh there we go this should be easy however it shows both songs that are duplicated therefore double the library. how can i get rid of these duplicate songs without having to click on every 2nd song all the way down and removing it. and also when i right click and clear will it remove the song completely as last time when i used to have a proper My Music/Itunes setup i lost alot of songs when i decided to "Clear".

Anyway sorry for the blabbering on but i hope i made at least enough sense that someone can understand and help me out as that would be much appreciated.
Thanks, Daniel