Seeking a guide on searching for apps

I'd like to see a guide on how to best search for apps. The problem: I want an app that does something specific. Right now, I'd like to find something that simply chimes when I'm connected to a wi-fi network and chimes differently when I'm not connected. But searching for terms like chime and wi-fi is going to find thousands of apps. Previously, I was seeking a recording app that just saved the last couple of minutes of what was recorded. I found epiphany, doing an advanced google search, and added it to the app directory here. However, I'd like more tricks up my sleeve. It would be great if the guide listed websites, search engines and advanced ways of using iTunes and the app store app to improve searching for specifics. It could also include a section on searching AppleVis. Though I find searching Applevis pretty easy, some beginners might not.