If your hybrid fits you and you like it there isn't any reason you can't tour on it. Often the gearing is low enough on a hybrid and you can use a trailer rather than panniers/racks just to keep things simple plus you may find the trailer useful at home to haul stuff around. The only thing that will likely need replacing is a stronger rear wheel that can handle your weight + your cargo. If you are good at getting deals [Ebay, Craig's List, etc..] you should be able to get something that works for a reasonable amount of $$$.

If you really enjoy touring you'll be in a better position down the road to know what you want from a touring bike.