Additional Site with Club Links
Here are a few sites with a page of links to ukulele clubs and societies. There might a few ukulele clubs listed on those sites that are not here. However, my site seems to include a little (a lot) more information that simply a listing of links.
Additional Club Resources
Some music stores might offer a club discount to active members.
The Ukulele Section right here has a ton of information, links, resources, lessons, TABs and Song Resources.