Its a little bit of a paper shuffle, but not much.
And you can attend meetings, but most people don't. The meetings usually have to do with the actual operation of the club as a business concern.
In general, you need to be nominated by a member. But most clubs want more members, so its not really a big deal. If there are no people you like there, you don't want to be a member.
I won a life membership in a yacht club by setting the elapsed time record in their big deal annual race. That's one way to do it.
In other clubs, I will attend some party at the bar, and express some interest, and you can get all the paperwork signed and accepted in a few minutes, assuming again there are people you know.
All clubs are quite open about their social calendar. All seem to be happy to show you around if you show interest.
In late April, there is a sailboat race to Ensenada that starts off the Newport Harbor jetty. Its the last friday of April usually.
http://www.nosa.org/
The Thursday before the race, there are big raft parties at all the clubs in Newport for sure. Easy to pull up, go in, meet people. Lots of powerboat people, its not just sail boat people. On Friday, several hundred boats head off to Ensenada. Dozens of powerboats, hundreds of sailboats. We are intending to do it this year, my boss usually takes his 48 foot cruiser down.
A couple of years ago we stopped at San Diego Yacht Club instead of going all the way to Ensenada. Club was in a welcoming mood, lots of fun, stayed the night in a slip, used the YC showers in the mornings, had a great brunch, then headed home. Good to leave early, as the wind comes up, and the chop builds during the day on the way back to LA.
Any time there is an open door, mention you'd like to explore becoming a member. Any time there is a party, meet people, if you like them, great!
If you ever get to Hawaii, those yacht clubs are quite social, and they have good membership programs (cheap!) for non-residents like me. Party, join, you'll probably save the dues on the cheaper bar bill before you head home. That's how I justify it.
My club is Waikiki Yacht Club. Many people who are members and/or visitors of lots of high end clubs claim its the best in the world. I like it.
To join Waikiki or Hawaii YCs when on Oahu, I tell everyone to do this: show up at the WYC or HYC docks on Friday at 4:45 with a six pack, hop on one of the sail boats that are going out for the Friday Night Race, and have a damn good time. Doesn't matter if you know how to sail, just matters if you know how to have fun. Enjoy the Aloha.