Robmar has some great advice. If you are going FOWLR
, you could get by with out the skimmer and use the money for other equip/critters.
I would also suggest getting
garlic (helps the immune system and stimulates feeding)
selcon (both are great additives for healthier fish)
get a refractometer instead of a hydrometer, easier to read and much more accurate, IMO
What size tank are you thinking?
As for fish, I like to browse liveaquaria.com for ideas, there is also saltwaterfish.com, thatpetplace.com. I generally get most of my equipment from drsfosterandsmith.com. Take a look at those sites and any other to get an idea.