Shop furniture closeout stores and antique stores to find a piece that can serve as a cabinet. Look at armoires, china cabinets and chests of drawers with "new eyes." Picture how they can be converted into a cabinet for your audio and video equipment. Put shelving strips inside the existing furniture to add shelves, adjustable to the height you need.
If you would like a unique look and are not afraid to be creative, consider using doors to form the side panels. This will give the cabinet a look that is all your own. Doors vary in width, which can also give you the advantage of creating a wide cabinet that is perfect for the television. Attach shelve strips on the interior side of the panels so that shelves can be adjusted to the height you need. Paint the doors to match wall colors to blend in with room décor, or stain to give the cabinet a wood finish.
A simple solution is to use metal shelving strips and mount them on the wall. The strips are available at most home improvement centers. The advantage is that the strips can be cut to any length you want, and you can adjust the shelves to the height you need. You can also paint the metal to match the wall color if you want to camouflage the strips.
Another variation of the "simple solution" is to use cubes or even a short-height cabinet. This way you have a sturdy foundation to hold heavier equipment such as a television. The cubes can be painted or stained to match walls. Many home improvement and furniture stores sell ready-made cubes in basic colors like black and white. You can also shop for ready-made cabinets. Look for cubes that are open or cabinets with storage space. That is where you can store DVDs, CDs and other items. Install shelving strips on the wall and adjust shelf heights to accommodate speakers, DVD and CD players, recorders and other equipment.