Hey sjaguar13, I got a Casio in 1983 for $500...It was built like a tank but it would sound pretty lame today (I guess the piano and organ on it wasn't that bad), at least I didn't need a manual to play it.
My take on the difference between a Synth and a Workstation: Each keyboard has a different set of features but roughly I would say a Synth mostly just has sounds while a Workstation has sounds plus other goodies (like maybe a sequencer, effects, or a diskdrive). The idea behind the workstation is that you can do many things musically using one instrument (without the need for other equipment), perhaps even taking a song from concept to finished product on just the workstation.
Technically a workstation is a synthesizer in which you can produce complete musical tracks on via the synthesizer, sequencer and multi-effects units. Examples of workstations include: Korg M1, Korg 01/W, Korg Triton, Kurzweil K2500, Kurzweil K2600, and so on.
When I searched through workstations, it brought up things like The Something Synthesizer. I guess I am looking for a synth. I don't really want to produce a whole song on a keyboard.
Most synths now days are workstations as the norm. The more features of course the higher the price. You could get a Triton LE that's probably the cheapest out. But if your looking to upgrade later get something else. I know sometimes you think yeah this is all I need and then kick yourself in the behind when you want to upgrade and you can't. I did that with a PC. Just make sure it's going to suit your needs.
Respectfully, I have to disagree with that statement. There are more synths that AREN'T workstations than are. Each of the big three (Roland, Korg, Yamaha) have a workstation series- Roland=Fantom, Korg=Triton, Yamaha=Motif, but most of their other offerings are not workstations. The smaller manufacturers like Novation, Nord or Moog don't offer workstations at all.