I'll be playing through my bands set just fine, but by the end of the last song my voice starts just getting terrible and wimpy and like i cant keep it at the same level i was keeping it at. What are some thing i can do to help this. http://www.youtube.com/watch?v=h2JOG1W5W9c here's a vid of what im talking about, at the very end, just like, my voice is drained.
Hold back at the beginning and don't give it your all right from the start. Start to build up during the set and then you'll have some of your voice left to do the last song.
"Don’t be a guitarist. Be a musician."

Steve Howe
Had a similar problem happen recently. Put all effort into the second last song and was completely drained on the last and sounded kinda half-assed.
WHAT do you want?
Learn good vocal technique. If you are using good technique, your voice will actually be *stronger* at the end of a show, end of a tour, etc. than it was at the beginning.

Could I get some more talent in the monitors, please?

I know it sounds crazy, but try to learn to inhale your voice. www.thebelcantotechnique.com

Chris is the king of relating music things to other objects in real life.