Just how many episodes does Melancholy of Haruhi Suzumiya has?

Ok so unlike naruto that has always new episodes coming every thursday this anime seems a bit confusing to me. So I watch it on youtube and completed like season 1 & 2 but i dont get it, is that all? is it complete already? I just dont get it! its so short and the isn't seem complete yet. Could someone pls give me the complete episode list? or from which site I can watch all the episodes of it (i want ALL episodes or even its upcoming episodes) Is that really all? it ends when Kyon revealed that 3 of the brigade members are alien,time traveler & Esper. Is that it? no more upcoming episodes?