How can you get front row tickets before they come out for an affordable price?

Me and my friend Rachel really want to go to the Jonas Brothers next tour and we want first row tickets but we don't want to pay 300 a piece! we wanted to know if there is anyone who knows a good website to get them like a month before they come out or anything because we really want to see them at the indy concert and cant really figure out how we are going to get them!