HT1766 Finding a recent backup (Recovering data after app sync fail)

Question

Hi there.
I have searched EVERYWHERE, downloaded programs, copied copies, and I still can't recover my data.
Here's what happened:
On June 15, Before I went on a long trip, I synced my iPhone 4. I'd synced it the day before (June 14), but I wanted to add a new song. 
Since I hadn't updated any apps, I unchecked "Sync Apps" in my iPhone's menu in iTunes.  I am almost 100% positive that I checked "Keep Apps" when the alert popped up.
(FOOLISH MORTAL.)
We're on the road, and I am horrified to see that all my third-party apps are GONE.
When I get back from the trip on June 18, I rush home to sync all apps, making sure to re-check "Sync Apps".  Happy day, they were back...until I realized that all data on my third-party apps was GONE.
Not just preferences and saved passwords...but two years of budget records from my Tip Sheet app.
I decided this whole thing could be easily solved by restoring my phone to the June 14 backup.  But where was it?  When I went to "iTunes > Preferences > Devices", there were a few backups, but aside from the June 18 backup, all other backups listed were from March and earlier.  This made no sense to me, as I back up my device daily, both to my computer and through iCloud (though most recently on my computer, as iCloud started telling me I didn't have enough space to backup - so there's also an older backup on iCloud).
I begin my research and learn that iTunes only rarely creates a brand-new backup treats its backups like Time Machine, in that it updates the backup with only changed information.  But, unlike Time Machine, there doesn't seem to be an easy way to access a recent, but not most recent, backup.
All I really want is my data from Tip Sheet, a third-party app, which was apparently lost in the June 15 backup, but must be salvagable.  If I go to "Users/[me]/Library/Application Support/MobileSync/Backup", open the most recent backup folder itself, and delete all files in the folder modified after June 14, and then try to restore my phone from that backup, iTunes gives the error message that my "backup is corrupted".  When I put the files back in, the backup works, but the data is still not showing up in my app.
HELP ME PLEASE.

Answer 1

Forgot to add: 
I did use Time Machine to look into backups, and on June 14 I had backed up using TIme Machine...but the most recent folder in its "MobileSync/Backup" was Last Modified May 15(?!) and, sure enough, when I replaced the old folder with the new and Restored from Backup, the TIp Sheet data was there - from May 15 and before.
A month might not seem like much, but that's a lot of data that would be hard for me to replace.  I know that at least part of my June 14 backup is somewhere in the most recent jumbled-number folder of backup files dating back to October 2010, when I got my phone.
Any insight into this matter would be much appreciated.