Is there any books discussing how the First World War was financed? How were funds spent throughout the war? How were they raised? How far reaching was spending all of that money?
Apologies for not answering this question earlier. Holidays got in the way. =)
The current go to book for this would be Hew Strachan's Financing the First World War, which is itself an edited chapter from his mammoth work To Arms. It discusses the financial arrangements of the main combatants on both sides through to the end of the conflict.
For a more in-depth discussion of Anglo-American economic cooperation, and British efforts to raise capital and purchase supplies in the United States, you might want to pick up Kathleen Burk's Britain, America and the Sinews of War 1914-1918.
Nicholas Lambert's Planning Armageddon, as recommended by u/CptBuck, is an excellent book, but its focus is on the British Admiralty's abortive preparations and efforts at conducting economic warfare between 1910 and 1916. The combatant's efforts towards financing the war is not its strong point.
For a thorough discussion on the banking crisis and near collapse of global financial markets on the outbreak of war you might want to take a look at Richard Roberts' Saving the City: The great financial crisis of 1914.
If you can read French, Georges-Henri Soutou's L'Or et le sang: les buts de guerre économiques de la Première Guerre mondiale is a highly rated mammoth work on the economic policies of both sides. Sadly, it has never been translated into English.
For shorter and more easily accessible texts you might also want to take a look at Part III (chapters 12-17) of the second volume of The Cambridge History of the First World War, edited by Jay Winter.
edit: fixed a typo
I can think of two that might be of interest. The first is Planning Armageddon: British Economic Warfare and the First World War, which looks at both the British financing of the war as well as their plans to how to ruin the finances of their enemies. As London had a near monopoly on global capital markets when the war broke out, I think this would go a long way towards answering your questions.
The second book is When Washington Shut Down Wall Street: The Great Financial Crisis of 1914 and the Origins of America's Monetary Supremacy which, as the title suggests looks at the American role in financing the war, and how capital began to shift from London to New York as a result.
If you're still looking, try The Economics of World War I. It discusses all major nations separately and nicely