It depends on the kind of tux and if you want designer or not. The tuxs for our wedding were nice but nothing fancy and were around $60-$70 each, but some of the designer ones (Pierre Cardon, etc) were around $150-$200. Forget that! I was lucky enough to even get my husband in a monkey suit, I wasn't going to push it!
Our tux rentals were $69 each. They were regular $99 but we had a coupon from a bridal show for $30 off each tux. My fiances tux was free but he had to pay a deposit of $40 on it.