We contracted for two magicians and a caricaturist through this Boston-based entertainment provider. They were friendly and gave a prompt response to an email inquiry. Over the phone they tried very hard to sell us things we did and didn't want. Overall we came in a little above budget, and I suspect they got a tidy profit above each entertainer's fees.
Even though I always feel guilty hiring a middleman, they did find an excellent caricaturist and decent walking magicians for us, and I'd do business with them again.