I think it's a bit late to register ahead of 
time, you may be able to make a 'reservation' for 
registration, check their website (www.anime-
expo.org).  You can register at-con.  

I find that there's enough things I am interested 
in on multiple days that I buy the four-day 
pass.  You can check the schedule on their site 
and see which days you would like to attend.

The convention center is pretty big and there are 
things going on in some of the nearby hotels as 
well.  I remember getting a fair amount of 
walking in last year.

I suggest bringing money so you can shop and 
eat.  If you're coming to the Cel Meeting, please 
bring your cels ^_^ (some of them at least).  You 
may also want to bring a camera to photograph 
cosplayers and other interesting people (but 
please be kind to the guests, some of them are 
very camera shy or sensitive).

Hope this helps!  I'm sure I'm forgetting 
something...
Keys