Look into and consider the reputation of whomever it is that you will be hiring to sing at your wedding. You want to make sure that they are able to perform the songs that you want at this special occasion. Try them out and see if they are able to meet your needs and expectations.
Remember that appearance is not everything. Sure how someone looks leads us to many conclusions, but as far as vocalists are concerned it is something that leads to maintaining their style and identity. It is in keeping up with their image that they present themselves the way that they do.