I won't attempt to answer everything, Oaktown Dancer, because my experience with comps is somewhat limited as well. So I'll leave some answers for the more experienced folks to make.
Going to a comp as a spectator is, IMO, always a good idea. You'll get to see beautiful dancing, and you can network and socialize with people like you, who love dancing. You may also meet some local instructors that interest you. On the other hand, some of these comps attract teachers and students from quite far away as well, so the teachers that you see dancing may not be available to you.
Going to this comp is as good a way as any to start. Have fun. It's the weekend of Palm Sunday, April 2 - 4, right? I hope you check in and let us know how it went. It will be interesting to hear your perspective.