Jcool pointed out this contest, the Alamance Arts Council Brick Building Competition.
The hard part about this is that you have to be present at the event September 21 and 22 in Burlington North Carolina. I'm pretty sure we've got some NCLUGgers in the forum, or others who have been to BrickMagic, so at least some of you are able to get to this. If this applies to you, it seems from the rules that you can build pretty much anything that would be 18 inches x 18 inches x 18 inches for the younger age brackets (6-9, 10-14, 15-20), or 36x36x36 for adults (21+). $500 prizes for the younger ages and $1500 for the adult, with LEGO prizes for 2nd and 3rd places. Deadline for entry is September 7. Let's have three winners from Classic-Castle, and get one of your younger siblings for that youngest category!
Since there will likely be a relatively small number of FOLs from the active online community, you should have a really good chance, particularly if you're in one of the kid brackets (on the assumption that adults might be able to travel to this from a further distance) (for instance, I know of two prominent adult builders who are planning on making the trip down from a couple of states away, something much less likely for a teenager).