Yoda linked me here since I've published a book on Lulu and I'm not sure he has.
1. You upload the pages of the book in PDF, formatted exactly as you want them to appear in the book (including page numbers, etc.) You can also make a revision to your book and publish second, third, etc editions.
Front/back cover are done separately. Lulu provides templates or you can upload your own image (I've had troubles with my image no matter how I try to resize it, it ends up a bit distorted and blurred. Maybe I'm just retarded.)
2. Lulu supplies you with a free ISBN number as long as you agree to their terms (basically you can't sell the book for a cheaper price than you list it on their site anywhere else. You can still sell it other places, just not for cheaper.) They give you the ISBN image and you stick it on the first page of your book. If you don't agree to their terms or if you already have an ISBN previously, you can buy/use that yourself. Like I said though, their contract didn't seem too crazy like you are locked in and can never sell your book elsewhere though.
3. Lulu will list your book on Amazon for free. I believe the requirement is that you have to purchase a copy of your own book first. I can't find on the site where you change distribution, just the requirements. Look up ExtendedReach and GlobalReach. Extended is free, dunno about Global. Global is needed for BarnesandNoble and international Amazon sites (.ca, .co.uk etc)
Once you upload your book and it's all set up, the rest is automatic. You don't have to deal with orders or anything. No shipping or printing obviously (that's what you're paying them for.) The money just automatically shows up in your account. I've never withdrawn yet (that's what she said) since I only have $6.66 in my account, so I don't know what the process is. I guess they just mail you a cheque.
4. Haven't marketed, the only person who has bought a copy of my book was my girlfriend. No one is going to buy your book if you don't do it. Depends how much money you are willing to spend, or how hard you want to work, I guess. Lulu will even do that for you if you pay them.
Maybe the best thing about Lulu is you set your own price. It costs them about $6.62 to print and ship a paperback, and you just add whatever markup you want. If you sell retail (Amazon), subtract an extra $3 or so from your revenue (bookstore's markup, so better to sell on Lulu itself if you can.) $0.99 flat fee on e-books.
Was going to upload a bunch of images from inside my account for you but quite busy at the moment >_<
Any other info just ask, but I won't be checking the forum most likely so Yoda will have to pass on the link to me again 
. All this is probably in their FAQ anyway.
Lastly, shameless plug:
Thanks so much for the info! 
And I apologize for thinking it was Yoda who published the book. I remember someone here talking about publishing through Lulu and I just totally forgot that it was you, Yarcofin. Again, my apologies.
And the info you provided is tremendously helpful. It's easing my doubts and concerns about doing this. It seems like a much easier process than I initially thought. I'm sure there are still some headaches but it's not as bad as I thought it'd be.
I guess the hardest part is marketing and willing to put up some money to try and sell it. I expected that so I wanted to cross that bridge until we get there. But first, I want to try and upload something to Lulu.com once we're ready.
Thanks again for the info. And I'll definitely have futher questions whenever I hit a wall, so thanks for taking the time to help. I appreciate it.
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Now Playing: Golden Sun Dark Dawn, God of War Ghost of Sparta, and DKC Returns
Self publishing on amazon? First I've heard of this.
Does this lulu work in NA only or worldwide?
@ASK You can always upload to Lulu and choose not to publish your project / keep it private. Or upload some crap just to test how it works. You don't need a separate account for each book and it doesn't need to be the title of your book, you get one account and each book is saved as a different project. You can just paste 100 pages of gibberish into a word document and upload to get a rough idea of what it's going to cost you.
@gaminggeek, there is an option to set your currency to £, as well as € or US$
Hey Yoda, I had a question I wanted to ask you (and to anyone else who may know).
I remember you published a book on Lulu.com awhile back. I was looking into doing something similar with a group of friends and I wanted to ask how you did it and what we should do?
My main questions basically are:
1. How does the submitting process to Lulu.com work? Do we upload our files (all the pages, covers, etc.) to their website?
2. I know we have to get our own ISBN number. How much is it and do we need it for each book?
3. And finally, the question I wanted to know about most was upon submitting/uploading the files, how do we put up our book for sale on Amazon.com or Barnes and Nobles.com? And if someone wanted to order it, does Lulu.com handle the printing and shipment or do we have to do it?
4. Have you marketed your own book yet? If so, what were some best ways to get the word out there?
Sorry if I'm asking too many questions. We do want to try and get a publisher like Image Comics or TopShelf, but just in case it gets rejected by them we were looking into selling it through Lulu.com as a last result. So any help will be much appreciated.
Thanks.
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Now Playing: Golden Sun Dark Dawn, God of War Ghost of Sparta, and DKC Returns