is it possible to add custom RSS Feeds i have found two good free usenet indexers that have RSS feeds available and i am thinking they might be good to add as indexers as a lot of sites unless you pay for vip have a daily API Call Limit
No there isn’t the ability to add custom RSS due to the fact that each indexer does things slightly different which requires us to customize parsing for each one.
I believe you or someone else asked about these ones on the old forums, neither of these is any good for NzbDrone.
Newnzb.tv - RSS updates every hour, most sites update every 15-30 minutes, hitting them faster will probably piss them off and waiting an hour between hits will likely causes issues with DMCA.
NzbRss - Looks like the RSS is broken down per show, not by quality, this would not work well for NzbDrone.