I've found the easiest way to get the script is to go to the custom feed editor and go to advanced view and just copy and paste it. I've done two.
The Daily Kos:
class AdvancedUserRecipe1221672989(BasicNewsRecipe):
title = u'The Daily Kos'
oldest_article = 2
max_articles_per_feed = 100
feeds = [(u'Main Feeds', u'http://feeds.dailykos.com/dailykos/index.xml'), (u'Diaries', u'http://www.dailykos.com/rss1/Diary.rdf')]
And The New York Times. I added 64 of 65 feeds available (the daily knowledge one is through feedburner.com and is not supported through Calibre). It's big and unwieldly so I would suggest taking off as many feeds as you can and are not interested in when adding it
class AdvancedUserRecipe1221673018(BasicNewsRecipe):
title = u'The New York Times'
oldest_article = 1
max_articles_per_feed = 100
feeds = [(u'Main Page', u'http://www.nytimes.com/services/xml/rss/nyt/HomePage.xml'), (u'Business', u'http://www.nytimes.com/services/xml/rss/nyt/Business.xml'), (u'Business - Media & Advertising', u'http://www.nytimes.com/services/xml/rss/nyt/MediaandAdvertising.xml'), (u'Business - World Business', u'http://www.nytimes.com/services/xml/rss/nyt/WorldBusiness.xml'), (u'Business - Small Business', u'http://www.nytimes.com/services/xml/rss/nyt/SmallBusiness.xml'), (u'Business - Your Money', u'http://www.nytimes.com/services/xml/rss/nyt/YourMoney.xml'), (u'Business - DealBook', u'http://dealbook.blogs.nytimes.com/rss2.xml'), (u'Education', u'http://www.nytimes.com/services/xml/rss/nyt/Education.xml'), (u'Health', u'http://www.nytimes.com/services/xml/rss/nyt/Health.xml'), (u'Health - Research', u'http://www.nytimes.com/services/xml/rss/nyt/Research.xml'), (u'Health - Fitness & Nutrition', u'http://www.nytimes.com/services/xml/rss/nyt/Nutrition.xml'), (u'Health - Money & Policy', u'http://www.nytimes.com/services/xml/rss/nyt/HealthCarePolicy.xml'), (u'World', u'http://www.nytimes.com/services/xml/rss/nyt/World.xml'), (u'World - Africa News', u'http://www.nytimes.com/services/xml/rss/nyt/Africa.xml'), (u'World - Americas News', u'http://www.nytimes.com/services/xml/rss/nyt/Americas.xml'), (u'World - Asia News', u'http://www.nytimes.com/services/xml/rss/nyt/AsiaPacific.xml'), (u'World - Europe News', u'http://www.nytimes.com/services/xml/rss/nyt/Europe.xml'), (u'World - Middle East News', u'http://www.nytimes.com/services/xml/rss/nyt/MiddleEast.xml'), (u'U.S.', u'http://www.nytimes.com/services/xml/rss/nyt/US.xml'), (u'New York / Region', u'http://www.nytimes.com/services/xml/rss/nyt/NYRegion.xml'), (u'New York / Region - The City', u'http://www.nytimes.com/services/xml/rss/nyt/TheCity.xml'), (u'Obituaries', u'http://www.nytimes.com/services/xml/rss/nyt/Obituaries.xml'), (u'Science', u'http://www.nytimes.com/services/xml/rss/nyt/Science.xml'), (u'Science - Environment', u'http://www.nytimes.com/services/xml/rss/nyt/Environment.xml'), (u'Science - Space & Cosmos', u'http://www.nytimes.com/services/xml/rss/nyt/Space.xml'), (u'Sports', u'http://www.nytimes.com/services/xml/rss/nyt/Sports.xml'), (u'Sports - College Basketball', u'http://www.nytimes.com/services/xml/rss/nyt/CollegeBasketball.xml'), (u'Sports - College Football', u'http://www.nytimes.com/services/xml/rss/nyt/CollegeFootball.xml'), (u'Sports - Golf', u'http://www.nytimes.com/services/xml/rss/nyt/Golf.xml'), (u'Sports - Hockey', u'http://www.nytimes.com/services/xml/rss/nyt/Hockey.xml'), (u'Sports - Other Sports', u'http://www.nytimes.com/services/xml/rss/nyt/OtherSports.xml'), (u'Sports - Pro Baseball', u'http://www.nytimes.com/services/xml/rss/nyt/Baseball.xml'), (u'Sports - Pro Basketball', u'http://www.nytimes.com/services/xml/rss/nyt/ProBasketball.xml'), (u'Sports - Soccer', u'http://www.nytimes.com/services/xml/rss/nyt/Soccer.xml'), (u'Sports - Pro Football', u'http://www.nytimes.com/services/xml/rss/nyt/ProFootball.xml'), (u'Technology', u'http://www.nytimes.com/services/xml/rss/nyt/Technology.xml'), (u'Technology - Bits', u'http://bits.blogs.nytimes.com/rss2.xml'), (u'Technology - Personal Tech', u'http://www.nytimes.com/services/xml/rss/nyt/PersonalTech.xml'), (u"Technology - Pogue's Posts", u'http://pogue.blogs.nytimes.com/?feed=rss2'), (u'Washington', u'http://www.nytimes.com/services/xml/rss/nyt/Washington.xml'), (u'Arts', u'http://www.nytimes.com/services/xml/rss/nyt/Arts.xml'), (u'Arts - Design', u'http://www.nytimes.com/services/xml/rss/nyt/ArtandDesign.xml'), (u'Arts - Music', u'http://www.nytimes.com/services/xml/rss/nyt/Music.xml'), (u'Arts - Television News', u'http://www.nytimes.com/services/xml/rss/nyt/Television.xml'), (u'Automobiles', u'http://www.nytimes.com/services/xml/rss/nyt/Automobiles.xml'), (u'Books', u'http://www.nytimes.com/services/xml/rss/nyt/Books.xml'), (u'Book Review', u'http://www.nytimes.com/services/xml/rss/nyt/SundayBookReview.xml'), (u'Dining & Wine', u'http://www.nytimes.com/services/xml/rss/nyt/DiningandWine.xml'), (u'Fashion & Style', u'http://www.nytimes.com/services/xml/rss/nyt/FashionandStyle.xml'), (u'Fashion & Style - Thursday Styles', u'http://www.nytimes.com/services/xml/rss/nyt/ThursdayStyles.xml'), (u'Fashion & Style - Weddings', u'http://www.nytimes.com/services/xml/rss/nyt/Weddings.xml'), (u'Home & Garden', u'http://www.nytimes.com/services/xml/rss/nyt/HomeandGarden.xml'), (u'Jobs', u'http://www.nytimes.com/services/xml/rss/nyt/JobMarket.xml'), (u'Magazine', u'http://www.nytimes.com/services/xml/rss/nyt/Magazine.xml'), (u'Movie News', u'http://www.nytimes.com/services/xml/rss/nyt/MovieNews.xml'), (u'Movie Reviews', u'http://www.nytimes.com/services/xml/rss/nyt/Movies.xml'), (u'Real Estate', u'http://www.nytimes.com/services/xml/rss/nyt/RealEstate.xml'), (u'Theater', u'http://www.nytimes.com/services/xml/rss/nyt/Theater.xml'), (u'Travel', u'http://www.nytimes.com/services/xml/rss/nyt/Travel.xml'), (u'Travel - Escapes', u'http://www.nytimes.com/services/xml/rss/nyt/Escapes.xml'), (u'Week In Review', u'http://www.nytimes.com/services/xml/rss/nyt/WeekinReview.xml'), (u'Most E-mailed Articles', u'http://www.nytimes.com/services/xml/rss/nyt/pop_top.xml'), (u'Multimedia', u'http://www.nytimes.com/services/xml/rss/nyt/Multimedia.xml'), (u'Editorials / Op-Ed', u'http://www.nytimes.com/services/xml/rss/nyt/Opinion.xml')]