Yup. Check around your area for local, privately owned mom&pop pet shops that carry fish. Often they'll take your fish for store credit that you can used towards supplies and such.
If all else fails, theres always the option of advertising on Craigslist...
I do agree that bettas do limit your stocking options, but personally I wouldn't advise against it necessarily.....instead, I suggest you just really do your research. If you don't mind the limits with stocking options that come with bettas and/or you are looking for a tank with just some very small peaceful schooling species like Tetras or Rasboras, or if you'd like to start something like a Sorority then by all means go for it.
But definitely look into all your options to make sure thats what you want. Find a few species you like, and research research research!! Research until your head hurts and research some more! I can't stress enough the importance of research when you're stocking any tank.
Personally, I wouldn't really recommend Gouramis over bettas either really. While they were not bred to fight and are generally a little less aggressive, depending on the species they can still be just as mean and aggressive as any betta. I had a blue Gourami that completely destroyed my tank, killed EVERYTHING.
So again....research research research!