Formally, the way to attend Comdex free for just exibits-only is by qualifying for a press pass (you show proof that you work for a computer publication by showing that you have two published artciles). Otherwise, the exhibits-only admission is $50 this year.
Like stated before, the biggest problem with going to Comdex (as it is with Networld+Interop as well) is finding an open place to stay. A lot of Vegas Blvd. (The "Strip"

hotels remotely close to the convention venue are usually already booked for this event months in advance. At the last Interop, we found rooms at the Union Plaza at Fremont (technically, this is downtown Vegas....very old school). They have really cheap rates and will cut you deals if you pretend you're part of an organization. Only problem with this location is that it's definitely not walking-distance from the convention (sucks if you don't have a car; cabs are really expensive in Vegas).
I would probably recommend looking around at
Expedia to seach for rooms with good rates that are in the general vicinity of the convention hall.
Good luck!