Many people use lightweight bikes to do extended tours carrying tents, sleeping bags etc. They are not limited to credit card touring.

Any bike can be a touring bike, but some will be better in certain conditions than others. Read the stickies at the top of the forum page and you will find lists,
pictures and opinions about lots of bikes.

Be aware that you can tour on bikes not specifically called "touring bikes", for example, I pack lightly and ride mostly on roads so I can successfully tour on a Cervelo RS.
If you are starting out a Trek 520 is a great choice.