There are stud finders out there that will show you if you have found an electrical Branch circuit, low voltage, etc.. They do cost a little bit more, but well worth it.
The best way to do this is get a flexible camera to insert into a hole not much bigger then the goose neck for the camera. You can get them at Harbor Freight and most Big Box. Also you can get them through partsexpress.com, amazon.com, newegg.com. You could order it today and have it in your hands by Saturday, if you cannot find it locally.
Studs are easy to find. The only catch-22 is knowing if they measured 16" On Center from door or hallway openings, or measured 16" On Center from the end of the wall against an outside wall. The quickest way is to pull the cover off of an outlet box and look for the bumps at the top outside edge and the bottom outside edge. The opposite side is where it is attached to the stud. Then us that as your reference point and measure off 16", check for stud before cutting.
Since you will most likely need electrical up higher if there is already a outlet below that point, you can put in an outlet that allows you to connect it to a UPS with Surge Protection, such as the Tripp-Lite Smart1500LCD (just for an example, since that is the one I use for my A/V gear). You would plug in the Male end on the UPS, the Female end plugs into a recessed Male at the point where you will have your equipment. At the location for the tv, you would have a outlet to plug in say the TV.
Just remember to measure more then two times, before making any cuts, unless you are using custom made cabinets that you have ordered.
Post your pictures in your album, and start a Project Showcase thread, to show off your project and allow others that may consider the same concept, to use your example.