Panasonic Lcd Tv Model Tx 15 Lv1 As A Computer Monitor?

That particular Panasonic set is a 480p EDTV with pretty low resolution (854×480 max), and not suitable for use as a monitor. That is why it only has component, composite, S-video and coax only.
You can hook it up to a computer only if your computer has a video card with those kinds of analog outputs, or if you use a scan converter device to convert a computer’s VGA signal to one of those.
Personally I wouldn’t bother. I’d rather hook up a computer to a higher-resolution HDTV set, such as those that can do 1080p High Definition (which is 1920×1080) through a digital DVI-to-HDMI connection.