For road cycling and under $1,000 budget:
If you are "brand" conscious, then try craigslist for a used entry-to-middle level road bike. Make sure the bike is current model, so any service/parts are still available when needed. Pay attention to these two area: (1) Derailleur- Shimano Ultegra, 105, or Tiagra is your order of choice. (2) Shifter- make sure the bike is equipped with a combined brake/shifter (stay away from down-tube or stem shifter). Brand such as Specialized, GT, Trek, Giant, Felt, Litespeed, and etc are all trustworth brands.
If you don't mind the brand, then bikesdirect.com (a Texas online site) sells some old name bikes (Motobecane, Mercier, from France, Dawes, Windsor from England, even thought these brands are all owned by other than their original owner) that use decent-to-top-notch components (Shimano of Japan, SRAM of USA, Campaqnolo of Italy) at discounted prices (compared with your friendly neighborhood bike shop).
If you are new to the cycling, then getting a new bike probably is the better way to go. Make sure you select the right "size" of the bike that "fit" you (components can be changed/upgrades, but you stuck with the frame you chose). If you don't know what bike size you need, then visit several local bike shops will get you to the right direction.