You better believe it was awesome! Pouring over all of the concept art, seeing the pure imagination and child-like nature of the entire place etc - it was fantastic and quite affordable ($12AUD when I went in 2006).
Grave of the Fireflies was very sad, it also brought me to tears. Dang.
Which is your favourite?
I have a few. Nausicaa of the Valley of the Wind, while very different and less complex than the brilliant manga, is a favourite of mine and the second Studio Ghibli movie I ever saw (the first was Spirited Away - another great movie). Princess Mononoke is fantastic but darker than his other fare. My Neighbour Totoro is wondrous and amazing and Whisper of the Heart gets me right in the heart. *cough* Oh bother, I'd be listing nearly all of them if I kept going.