These are the diapers I would recommend trying. I would recommend getting a total of 12 diapers and 4-6 covers in any combination and see what you like the best and then buy more of that.
If you want to try prefolds
Chinese or Indian prefolds with Bummis Super Whisper Wraps or Flip one-size covers.
If you want to try fitteds
Mother Ease Sandy's bamboo (or cotton if you are more concerned about money than bulk) with Mother Ease Air Flow snap covers or Bummis Whisper Pants.
If you want to try hybrids
The Flip system and/or the Best Bottom system
If you want to try pockets
bumGenius or Fuzzi Bunz
If you want to try an all-in-one
I guess bumGenius, but I haven't actually tried any others