I love them too - I just copied a couple of their CD's to my Zune the other day. I remember how much I loved them when Rumours came out - that's one of the top 20 albums I'd pick if I was stranded on a deserted island - there's not a bad song in the whole thing.
My cousin, who's younger than me (he's still in his 30's), loves their early stuff - before Stevie and Lindsay joined the group.
Have fun tonight - I wish I was going with you!