I've tried searching for this since I feel very stupid asking, but no luck. On my new receiver, the volume level on the front panel ranges from -96.0dB, to 0dB. Please explain what this means. If 0dB is the loudest, how do I know what decibel level the sound is at? ("dB" is "decibel", right?)

Your manual should tell you what the db level is at 0. I don't there is an industry standard of what reference 0 is, but I think it's directly proportional to the wattage rating of the amps. Like on my receiver 0 is incredibly loud, I generally listen to movies at around -20db and music at around -30db and that is LOUD. However 0 is the midpoint on my receiver. The range is -60 to +60 so 0 is probably a reference setting.

My user manualy does say the db level at 0, it's in the specs section.

This is not a stupid question caiman, it is actually a pretentious practice on the part of the manufacturers. 0dB is considerd to be the established max level (input or output) of a system and everything below maximum is considered an attenuation and therefore measured in a negative fashion. I honestly don't know what the manufacturer is trying to display with the +/- 60 on your's palebluedot (this is not indicative of quality; I have known manufacturer's that use marketing types to design labeling and they many times use a "ours go to 11" approach).

In regard to how loud your system is you have fallen into a very common assumption. Decibels or dB are referenced units of measurement. Simply put, you determine your measurement application and reference one point to another point. It is not a fixed scale like inches on a ruler; it is a relative scale. What you are thinking of as how loud your system is, is actually dB of SPL or Sound Pressure Level. This is an established measurement situation exclusively used to reference how "loud" our ears perceive something to be and it usually uses a "weighted" scale. The scale on your volume control are degrees of attenuation from max output. The crossovers in your speakers are rated at a level of attenuation over frequency of the input signal.

This may seem confusing, but maybe the origin of the measurement will help. Way back when, after the telephone was proven to work, the long laborious process began of installing our country's (and also the world's) phone system. It was very soon discovered that signal integrity was lost over distances of wire and routing and to maintain the signal, it would have to be boosted at points along the way. The problem was to know how much signal was lost so you knew how much amplification to apply. This was point to point measurements. For instance: How much signal was lost from the main town switchboard to your house? Or to the next town? The type of scales in use at the time could not be effectively used for this very specific application, so a new on was created named after the system's founder: the Bell (as in Alexander Graham).
And so ends today's history lesson.

-Shawn

Thanks a lot guys. Very helpful! (and interesting).

A few last minute thoughts:

If you really want to know how loud your system is, you can buy an inexpensive SPL meter (I know Radio Shack has one) to get a good ball park. Please wear hearing protection if you do this! Also be careful of using extremely dynamic material to do this to avoid potential system damage.

This is not something I honestly recommend people do. The purchase of the meter can be a good investment if you want to get your speakers dialed in level-wise and I do highly recommend that.