Head to Golden on a weekend day and just get in the water. Meet some paddlers in the eddies and I guarantee they'll take care of you. I don't mean to suppose that it's everybody's responsibility to bump boats for novice swimmers, but that folks there will happily help and give suggestions.
Lots of times when I have no one to boat with I'll boat Golden because I feel ten times safer with all the knowledge around.
And hey, Golden is only like 10 minutes past Confluence for you, just go there! And Union chutes is the closest boating to you, not confluence.