$500 total to get into vinyl, what would you buy?

The Rega P3, MMF-5, Pro-Ject, and VPI Jr. can all be had, with a decent arm, for around $500 used. Any of these should meet your needs nicely.

Like Sdcampbell, I would agree with the MMF 5. In fact, I'm picking up one myself in about a week or so. It will be my first table. A good one to start with.

If you need to buy a phono section in addition to the analog rig, you'll need to consider at least $100 for that.
I think a Planar 2 with a lower cost Goldring cartridge and a Parasound or Sumiko phono stage, could be gotten for under $500 for all of it.

This would just barely be getting you into a decent quality rig, and would not really be representative of what vinyl can be, but would be a good start. The tonearm would be the best part of the rig, and could be modded to take you quite a ways up the scale, moved on to a higher table. Everything else could be considered expendable when you upgrade.

About 8 months ago purchased a used MMF-5 TT in pristine condition and am very very pleased with it. I like the fact it comes a very good cartridge standard and offers very good platter isolation.(Something to consider if you have kids or if people's footsteps around your rig are an issue.) My TT does have one design feature with the cueing mechanism which you have to be careful about. Namely, if you bring the tonearm too far to the right(away from the platter) the cueing arm/level in the "up position" will not prevent the arm/cartridge from hitting the base. Perhaps newer models are different? Just have to exercise a little extra care. Overall, a great TT and a wonderful way to re-discover/discover vinyl.

Hi Socrates, once in a great while I have seen the Well Tempered TT with the W.T. tone arm for $500. An excellent TT even if you may have to spend an extra $100 or two. Keep an eye out. Not one of the best looking TT but will compete or better many high priced CDP. Like Kotta said "A wonderful way way to re-discover vinyl". IMO, a true classic. Good hunting.