There are lots of inputs on the back behind the cover. Three inputs (1, 2, 3) have an S-video, composite video (A/V) and component video jacks. The cover will come off if you press the two top hook at the top of the cover. Then rotate the cover towards you. There are also a DVI-D port and 2 coax (antenna in) jack. The tuners included are for NTSC (analog OTA) and CATV (analog cable). The front of the PC (VGA) and a S-video or composite (A/V) video input (called Input 4).
Composite and component video jacks are all RCA jacks (as are the associated audio jacks for the input). Composite cables uses three RCA plugs on each end - yellow for video, red and white for Right and Left audio. Component video cables have three plugs on each end that just carry video (red, blue and green); the audio is wired separately with just 2 RCA red/white plugs. Match your colors from the device out to the TV input.
Changing inputs can be done with the remote or the input button on the top of the TV. The input button is to the left of the power and Main Power buttons.
Connecting your game system, cable system and all will depend on the units. For the best picture, use component video cables for mose set top box. Some cable boxes have a DVI port - use that if the box has that option. If they do not have component video out, then use composite or S-video cables.
The owner's manual is available from Sharp as a pdf: http://www.sharpusa.com/CustomerSupport/ProductDownloads.aspx?downloadtype=ownersmanual
. Use the drop down menus as follows > LCD TV, Model not listed, LC-30HV4U then click Search. The picture of the inputs are on page 10.
I hope this helps.