best used inexpensive cd only player

I would agree with the Rotel , but a CD player is a unitasker as Alton Brown would say.
I would go with a good dvd player and have a multitasker, who knows this may turn into a HT/2 Ch system at some point.
The Rotel 1093 has been an excellent player for me 24/96, and offers outstanding video to boot!
I think the power supply has alot to do with its sound and picture quality.

"Joe Mazzaglia makes a good inexpensive one".

ABSOLUTELY agree with this statement!

Everyone's tastes vary. I find Music Hall players very dull and boring. I've heard them suck the life out of many very good systems.

For about $500, it doesn't get better than a Rega Apollo IMO. They were going for around that price a month or two ago, but have been creeping up for some some reason. Maybe the economy really is getting better? The Planet 2000 is an excellent player as well.

To be honest, I'd go with an inexpensive transport and a DAC. The universals like an Oppo aren't a bad idea, but I haven't heard them. Connect them to a good DAC, and you've got music and movies sounding great.

There are a tone of DACs out ther that'll fit your budget, new and used. I got into the music server thing last year and bought an Apple TV and Theta Cobalt 307. Sounds great to my ears. No looking for discs, changing discs because I want to hear one song, etc. In some ways, it sounds better than my Apollo. My Apollo has a better toe tapping quality to it, but its not that far behind. Last I looked, there was a Theta Cobalt 307 listed for $150 with everything included. Add an Apple TV (with internal hard drive, not the new one) and an iPod Touch to use as a remote (if you don't want to use the Apple TV's remote and your TV), and you should come in right at your $500 budget.

Just to add...

I compared my Cobalt 307 to a bunch of the current budget DACs on the market like the V-DAC and DAC Magic. The Cobalt 307 is about 15 years old and still beat them all in sound quality. While the DAC chip may be out dated, the torroidal power supply and discrete analog output stages aren't. Its not just the chip that you hear in a DAC.

I'm waiting on Rega to release a DAC before I'll upgrade. The Arcam rDAC at $479 looks very interesting too, but I haven't heard it. My dealer carries both brands, so I'll hear them head to head when Rega's come out (supposed to be $995).

I disagree with the anti Music Hall posts. I find it to be a very detailed clarion player that is a true giant killer. It is not the last word in CDPs I have since found fuller sounding players that image better but keep it for a second system. It is very hard to find one that can compete with it in that price category.

I have just found over the last couple of years if you are not in the 24/96hz (at least) game then you may be left behind.
My Atoll preamp has Burr Brown 24/96 dacs in it, and my B&k Ref 30 can hold its own in todays bits wars.
I have had a few stand alone Dacs in the past and they cannot compare.
Power supply or not.
Most top line DVD players now have excellent power supplies, Rotel especially.
20 bit is great (as some of the dacs mentioned above), but its not 24 or even 32 bit thats now offered.
Let alone 192hz.
And 48hz is on its way out the door!
You think new artists are going to record in 20bit/48hz?
I can say that if you are not on the 24 or 32 bit bandwagon now, you may be left behind in the next year or so.
Your going to be a few bits behind!
Looking ahead now may save you some money in the near future, both HT and 2ch, SACD, DVDA, Computer based, ect, ect,!
They are all moving in that direction.
I really have not noticed any manufacturer, recording artist, recording studio, microphones, pre-amps, amps, hometheater receivers, cd players, dvd players, processors, ect, moving back to 16-20 bits.
I have a feeling I know why though.
Just my 2 cents.