I'm having so many problems tryign to lightly tongue/legatto tongue. Are there any tips on how to do this/good ways to practice it. I get so fustrated and want to throw my clarinet out the window when i try to hold one note out and on a very low temp leggato tongue on every quater note.

I wrote a little on this topic in the last few days:

http://www.8notes.com/f/26_183187.asp

Ya gotta get a steady, vibrant tone on your mouthpiece and barrel before you have a chance on the full clarinet, and the same goes for legato tonguing. It must sound legato on the mpc and barrel first. It just makes sense! Most people make the mistake of moving their tongue too much, especially if they were poorly taught when starting out. Good Luck!