please help or at least point in right direction

[gnp]

I am streaming 100% legal content and want to stream both live and on demand. I have been streaming live with only issue being I cant preview video while streaming but what I am after is....

1 a way to cut in content from a second source durring live streamms (ie comercial type media files that are pre made) but it needs to run in such a way as to not disconect the stream that is in progress.

2 a way to set up a user/pass for paid clients for both on demand and live streams (while most streams will be free, a few will require a paid membership)

3 a way to overlay a logo or text on live streams like in the top or bottom right hand corner.

Any and all help is greatly appreciated, I was also wondering if there was an irc chat room set up anywhere I might be able to get a little help along the way.