I'd also recommend Advancedsubmitter or Dreamsubmitter, Dreamsubmitter might be a bit more difficult to use, but therefore it's more flexible to use, so both are some almost perfect tools.
Additionally you can try my
Manual Submission List if you just wanna play around a bit to get started.
And before you start to think about buying gallery spots I'd suggest that you gain some experience as a normal submitter first. Gallery Spots can be very profitable, but only if you know what you're doing, so take your time and learn everything for a few months before you start buying spots
