Most fish stores will sell fish to anyone, so if you're looking for a good home that's not a great option.
There really aren't that many fish rescues anywhere. I only know of a couple in all of the U.S. and they specialize in taking large fish that people can't house, though they will also take smaller fish sometimes to rehome.
Your best bet would be to find a local aquarium society and see if anyone would like some fish for their community setup. I'm sure there are some people with established aquariums that wouldn't mind some danios. You can also try finding a fishkeeping forum, or just a local forum to post and see if anyone with an established tank wants them (try craigslist maybe. A lot of people on there looking for and giving away fish).
As for the algae eater, do you mean a pleco (most likely), or a chinese algae eater? The latter turns aggressive and may suck the slime coat off of other fish, so fishkeepers tend to stay away from them. A pleco shouldn't be hard to rehome.