Yeah, pretty sure デコグッズ is a short for デコレーショングッズ, which literally means "decoration goods". たも is a kind of a fishing net, you can see what it looks like if you search for it in Google Images. I don't know what dictionary you're using, but for example jisho.org knows what it is. Or were you confused by the fact that it's written in katakana here? That's actually pretty normal, see here for more info.