Book Buying and the Budget

For a New Year's Resolution, the spouse and I have decided that we are going to strictly budget in 2008 -- that is, keep an record by month of what we plan to spend, and then record what we actually do spend. I'm interested to how this affects my book buying. I do buy a lot of books, but in all honesty, a significant percentage of them are impulse buys -- not really considered and planned choices. I was thinking of instituting a personal rule that I have to check books out of the library or at least see if the library has them before I buy them.
I buy most of my books at my local bookstore. They're not as cheap as Amazon, but I think it's valuable to support a local business, and I value the staff's recommendations and expertise.
Now -- oh joy, oh happy day -- it's my turn to pick the book for my book group this month. We rotate pics. There are two conditions: First, you can't get input from other people in the group. This is so we get a good variety of books without any picks "by committee." Second, no one can have read the book. We all come to the book fresh as new readers.
So with the budget in mind, I'm going to pick a book that I own but that I haven't read. Here are some of the possible contenders.:

• The Tin Roof Blowdown by James Lee Burke: Burke writes mystery novels set in Louisiana. This is his latest, set in post-Katrina New Orleans. It is supposed to be excellent with a literary bent, and I've never read him before.
  
• Mothers and Sons by Colm Toibin. Short stories set in contemporary Ireland; Toibin has superb reputation as a serious fiction writer. He recently wrote a fictional life of Henry James ("The Master") that got great reviews. The only thing holding me back from picking this one is that my last pick was a contemporary Irish novel -- The Sea by John Banville. I may pick Toibin anyway.
• The Ha Ha by Dave King. This is American fiction from 2005, about a brain-damaged Vietnam vet who befriends a little boy. The man doesn't speak, yet he narrates the novel. It's supposed to be a really good and has gotten great word of mouth.

I also have the following unread titles to consider:

• Generation X by Douglas Coupland: I've never read this novel released in 1991 that gave the name to my age cohort;
• Bayou Farewell by Mike Tidwell: Pre-Katrina nonfiction about Louisiana's vanishing coast line;
• A Werewolf Problem in Central Russia by Victor Pelevin: Short stories from one of Russia's best contemporary writers;
• New Stories from the South 2007 edited by Edward P. Jones: an anthology of last year's writing from Southerners.

So you can see I have quite a few choices. Feel free to comment and let me know what you think, excluding current book group members. I think I'm going to narrow it down to three books, then read the first chapters of all three, then pick one.
Update: This post has been amended. It originally said "The Ha Ha" was "about an autistic man who befriends a little boy." See comments for details.