Cough and saliva/mucus?

Ive had this wierd cough since Nov of 07. It does not hurt unless I cough too much. But today I could not stop coughing .I coughed so much that this thick spit/mucus came out.In my opinion the thickness was equal to slug slime( literaly) and when I looked at it it was clear but when I really looked at it I saw this white stuff in the clear spit/mucus. I need help. Its getting really annoying.