I'm a huge snacker. What I found that helped are to find healthy foods that have a "simialr" feel to my old foods to snack on.
For instance, instead of chips, that crunchiness I have substituted for celery and a little peanut butter. It's the crunch I like. I do the same with almonds, or pistachios. Now you do have to watch portion size, as you keep going you will get accustom to the new portions. Remember feeling hungry isn't an emergency! Drink lots of water too!
For sweet instead of cookies I do a Kashi Lean Bar, or greek yogurt with Kashi lean Crunch cereal and strawberries (my favourite) or fruits and raisons!
Just start to explore the healthy foods, see what you like and see if you can find something common in the texture that keeps your appetite. It takes some experimenting but keep at it and you'll figure it out
