>I'm not sure where to go next. I think Garrett's idea has some merit, but there are copyright
>issues to re-use another book's structure.

True, but the book is under the GFDL.

You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

*Use in the Title Page (and on the covers, if any) a title distinct from that of the Document...
*List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications...
*State on the Title page the name of the publisher of the Modified Version, as the publisher.
*Preserve all the copyright notices of the Document.
*Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
*Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
*Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document's license notice.
*Include an unaltered copy of this License.
*Preserve the section entitled "History", and its title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page....
*Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document...
*In any section entitled "Acknowledgements" or "Dedications", preserve the section's title, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein....
*You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version...
*The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

Hence, no copyright issues if we comply with the license. (And I did explicitly clear this with Pilgrim a while ago -- I just never went any further with it.)

As for who would publish it: good question. If we do a good enough job, we might be able to find a publisher like Apress: if not, there's always Lulu.com...