Wade,
I just started diving, and I LOVE the underwater park! And... I log it as a shore dive, even though it's an easy one. Here are a couple tips I gleaned from a recent article in California Diving News, that really helped me.
If you decide not to take a taxi from the landing to the dive park, you'll have to schlep your gear through Avalon. It helps if you put your gear in a big suitcase on wheels.
Catch the 6:15 am Catalina Express from Long Beach - that way you'll be one of the first to splash! The Catalina Diver's Supply van is located right at the park - opens at 8:00 am. They have tanks, air and weights right there. If you're first in line at the van you'll be finishing your first dive about when everybody else is lining up at the stairs. Then just wait for the first wave to exit the park and make your second dive. Also, the park often clears by 1:30, as people head back to the mainland on the 2:00 Catalina Express, so you might want to do a dive around 2:00
Bring a tarp to lay your gear out. Even though the ready area is paved, it's still gritty, and the tarp will save your gear.
Bring quarters for the lockers and showers. Lockers are extremely convenient and by putting valuables in there you can dive without a second thought!
Don't count on the bathrooms being open at the casino. They were closed for repairs last time I was there - about a month ago.
I like doing my last dive in the kelp at the north end of the park near the shore, in 25 to 30 fsw. Seems like there's a little current that comes through that makes visibility crystal clear, and my air lasts forever. While visibility is usually great throughout the park, it seems to be best up in that corner, where the current enters the park. Dr. Bill may actually wish to comment here, since he dives there all the time!
Hope that helps!
wetrat
Have fun! 
