French cleats are a simple way to hang things on walls while allowing easy repositioning. One bevelled cleat is fastened to the wall and the other is fastened to whatever you want to hang. One catches the other and gravity does the rest. French cleats are commonly cut at 45 degrees but I prefer to cut mine at around 30 degrees. This makes them easier to lift off the wall (especially way up high) without sacrificing security.
Woodworkers are a social bunch, and there are a few popular forums where people share thoughts on tools, discuss technique at length, and—of course—upload their plans. Some of the most active online woodworking communities include Lumberjocks, Woodworking Talk, Wood Magazine, WoodNet, Kreg, and Sawmill Creek. Search those to see if they have what you’re looking for (either with their built-in search tool or with Google’s site-specific search, e.g. site:lumberjocks.com side table).