When planning your wedding you reach out to lots of different vendors to find the best one for you and your wedding. You may email, meet with them in person, meet with them over Skype, or talk to them on the phone. When you find your dream vendor you are excited and can't wait to work with them on your wedding. How do you tell the other vendors that they weren't the best fit and that you've chosen someone else?
First, don't stress! As vendors, we know we will talk to a lot of couples and that we may not be the best fit for everyone! Although a vendor may have been excited and looking forward to working with you, they won't be super hurt if you choose someone else.
The best thing you can do is send the vendor an email and let them know that you've moved in a different direction. Thank them for their time and their help. If you feel comfortable letting the vendor know what the deciding factor was in why you choose another vendor (out of budget, wedding style, personalities didn't mesh, etc), let them know! Your vendor will appreciate the feedback.
All in all, just keep in simple, and let them know. Don't feel guilty about your decision, the vendor will know that you made the best decision for your wedding and they will appreciate the fact that you let them know!