Jwglista, what city are you in or close by? What music are you listening to?
Depending on where you are, I am sure there is someone in your are that will let you listen and could mentor you with vinyl. Finally, hit the local used record shops, browse and see what you find and whether it fits your taste.
For a basic estimate I would assume $500 for a good table, about $300-500 for a better phono preamp, another $200 to get started with cleaning supplies and accessoires. That will at least double as you dig in deeper.
Last but not least; Do you have the space for LPs? We are moving every 1-2 years and like to live in the city - moving 600-800 LPs is no joke and takes a large part of our small downtown loft.