I'd start at your local bike shops and ride different bikes within and maybe even a little over budget. That will give you a sense of the size you need and perhaps narrow down bike choices. From there negotiate with the LBS if you find a bike you like but it's over budget. If you can't negotiate it down to fit your budget then at least you have a size and a model to look for. Many of the 2017's will be on sale as the shops want to clear them out. If you find a new in stock 2016 you might be able to score a bike well over you budget for what you want to spend.

If that does not work out then you still have the knowledge of what size and bike you want, then you can start scouring for used ones.