I am about to start a study of the 1689 London Baptist Confession of Faith with a friend of mine. So I thought I would put together a list of optional resources. Of course there are many other resources out there, but these are the ones I've found most useful.
Right now I am primarily using the 1689 Android App put out by Puritan Soft. The proof texts are hyper-linked to a screen that will show you all of the proof texts for that particular paragraph in the ESV. It also has a nice "checklist" TOC that allows you to mark those sections you have read through.
I prefer the original wording* but if you are interested in a modernized version, check out the version done by Andrew Kerkham. No matter your preference of language, this particular PDF has the expanded proof texts put out by Sam Waldron, which I think is great for a group study when searching out proof texts will be an important part of your work.
*Greg Nichols makes an excellent argument for the original language in his introductory Sunday School series on the 1689. He states that the usefulness of the original language is in the use of the semicolon. Basically, the longer sentences allow the reader to find the main point and those points that modify it. When those longer sentences are broken up, the original main point is impossible to find.
There are numerous print editions out, but Chapel Library will send you a print edition for free. Just search "1689" in the literature search. They also have a nice PDF version for free as well.
Finally, here is a good comparison of the Westminster Confession (Presbyterian), the Savoy Declaration (Congregationalist) and the London Confession (Baptist). The Westminster was the parent document for the latter two, who changed various areas to comport with their ecclesiology and sacramentology. The beauty here is in the amount that these three groups, in the midst of persecution, could stand together on. There was, to a large extent, uniformity in their calvinism.
There is a book written by Sam Waldron that everyone says is fantastic. It seems to be out of print but CBD is still carrying it for a great price. The book comes in at close to 500 pages, so he's going to go through the Second London Confession (SLC) with some detail. I haven't read it (yet) but hope to soon. Maybe a review afterwards?
There is an online commentary of uneven quality (hopefully not for long!). The author has spent a lot of time writing a commentary through chapter 11, and has after that posted his rough notes for the other chapters. As of April of 2014 though, he stated he is going back and will finish what he's started. I don't know who he is, nor does he seem to state on his website (if I am wrong here, please let me know). That kind of thing always makes me a bit nervous.
Greg Nichols, waaaay back in 1985, taught an adult sunday school class on the SLC. I haven't finished it yet, but I have made some real headway through it, and it is quite good.
Background and Random Links
"The Legitimacy and Use of Confessions of Faith" by R. P. Martin
"How (and Why) your Church Should Hold to the 1689 Confession" By Sam Waldron
Two very helpful audio lectures by Michael Haykin on the "Men" and the "Message" of the SLC
As I continue to troll the internet, maybe I'll add to this as new things show up. Please add your favorite links about the 1689 in the comments below.