no need to name your samples differently and all this stuff, i think you're makin it too complicated man...
look the easiest way is have a folder called "beats" or whatever you like. in it, have a project folder for every beat, containing all samples used, sequencer files, mp3s of thebeat, whatever. name it whatever you like. all you need to do is drag your mp3s into itunes once done. just fill out their info appropriately...put your production name, maybe the month you made it under album (i do february 2007 beats, for example), rate it using the star system, enter the bpm. from then on, you have a completely searchable database of your beats that you can sort by date, genre, bpm, stars, whatever. and if you put anything in the comment field...i.e. "west coast" or an artist who you frequently work with who you think it would fit, put his name in the comments, because the comments are searchable. i don't know how you can keep your stuff as searchable and easy to find as this.
and when you need to retrieve the mp3, just right click the song's name in itunes and select "show in finder" (or whatever the equivalent is on pc). the song's physical mp3 file pops up, and it should be sitting in a folder next to all of the beat's files.