If its your first batch, don't worry about that stuff. Its far more important you concentrate on hitting your volumes and temperatures accurately to start - once you've got the basics down you can worry about conditioning your water.
A good "water rule" for beginners is that if your water is clean, doesn't have any odd aromas, and is nice to drink, it should make for good beers.
Now, that said...
If your water is cholorinated its not a bad idea to let it sit for ~24 hours. The chlorine will evaporate, reducing your risk of off flavours. Some cities using chloramines in place of chlorine - if you live in such a place you cannot simply evaporate this stuff off. Instead, you need to filter with an active charcoal or precipitate it out with metabisulfate. But unless your water smells quite strongly of chloramine this is an unnecessary complexity until you're a little more experienced at brewing.
If you have really horrendous water you may need to get a really good filter system, or even buy spring or distilled water rather than using tap.
Bryan
EDIT: I'm not trying to say that treating and worrying about your water is a waste of time or won't improve your beers. All I'm saying is that in the grand scheme of learning to brew, water quality is far less likely to be an issue that brewing processes, so the best use of your time/effort is to concentrate on your brewing method, and then to add-in water adjustments, etc, once you are comfortable with your brewing setup and process.