| Being a keyboard player also let me ask a couple of questions, are you looking for weighted keys or synth action keys? Can you or will you potentially hook it up to a computer? Do you have any intention of recording or playing on stage with what is in effect to be your learner keyboard? Are you going to take piano lessons?
These are all relevant questions. For example is the answer was synth and all no's I would say any old POS 61 key radio shack or casio will do, used at that. You can make noise and learn the notes, yeah.
If you want weighted action, the the prokeys88 is a great suggestion as are numerous stage piano setups, again look used. If you are going to take lessons find your teacher first. Some teachers refuse to teach on anything other than a real acoustic piano so right there your decision is effected.
If you are not going to hook it up to the computer, the Prokeys kind of looses some oomf, but still a good keyboard.
If you are looking to take it on stage and want a wealth of sounds that have good clarity yet a wide variety there are many great options.
Used I will mention the following 16 key synth action ones.
Korg X5 (and many other older korg line synths)
Alesis QS6 or even the newer 6.1
Kawai gear can be found used but many of them are additive synths which is you plan to learn synthesis might be steeper of a learning curve.
Emu PK-6 or Enqoniq Halo 6 - light, not that old, good sounds, great filters, difference, PK-6 has more patches, Halo has the perfect piano patch made famous on the Ensoniq ZR76.
Which brings me to MANY older Enqoniq keyboards that were great products and can be found used easily.
And lastly if you can find a used Kurzweil K series I would consider that as well. Even their synth action boards feel great under the hands and great sound selection and quality.
Ken | 
) but its fun none the less!
