Rumour Sources

Try to avoid having 100+ to avoid the libraryette card. Wait for the Call in favours in the Flit opportunity card to spend Connected: Revolutionaries in the Flit — 120 CP will earn you 720 Proscribed Material (28.80 Echoes). Perhaps one of best actions in this game. Or grind in Watchmaker's Hill, where A literary sort of fist-fight will net 25 per action. Doing 'The big one' in the Flit and choosing Rob the Ministry of Public Decency and then 'Rob the main archive' will net you 100, plus other goodies like stolen correspondence. In the Empress' Court you can get 20 per action through The life of the mind and then discussing politics at a salon. Slightly lower quantities (~20, though up to 40 per action at certain points) can also be obtained at various times and places in the The University for lower Watchful requirements. Several conflict cards will also gain you smaller amounts.

Convert from Proscribed Material. 31 inklings in addition to appalling secrets can be gotten from an opportunity with a nocturnal visitor to the Palace cellars 3+ at the cost of 250 candles.

Incendiary Gossip
Use Implacable Detective's Business card and play chess. A success gains 5 gossip from 100 secrets. Or convert from Inkling of Identity. sells for 50 pence

An Identity Uncovered!
Convert from Incendiary Gossip sells for 2 Echoes, 50 pence

Blackmail Material
Convert from An Identity Uncovered!, or wait for 'Wanted: Reminders of Brighter Days' card which allows you to convert 25 Incendiary Gossip for 1 Blackmail Material. Success also nets one An Identity Uncovered! Available from Another Strike or on a rare success for the Swap Incendiary Gossip card.

Diary of the Dead
Buy these from the Bazaar or use the The Relickers card. sells for 60 Echoes