Originally Posted by
ironwood
Why not start with the bike you have? You don't say what you presently own, but a lot of bikes are easily converted for touring. But then again, some aren't.
This suggestion above. Find some cheap racks and used panniers (or even duffel bags) and try some short 1-2-3 night rides in your area to see what works for you/what doesn't. It'll help you make a better decision on purchasing a bicycle