Except for a rare lucky find, you will have to enter arrangements yourself of the sort of stuff you describe. The general run of prepared BiaB numbers available for free is hackneyed and limited (and often none too legal).
In your field, you already see how you find the same old Realbook jazz heads over and over, and maybe a couple hundred overplayed standards. This fakebook search page will help you find legitimate leadsheets:
http://www.seventhstring.co.uk/fbindex.htmlYou can look for songbooks on eBay. I have found a number of useful bargains there. People mostly want the same popular thing, so interesting books may go cheap. Music stores sometimes have some old and unusual stock.
Downloadable sheet music is also online from a number of sources. That can get expensive, but sometimes it's the sensible way to get a scarce thing; buy a leadsheet for 3 bucks.
Bob Norton has entered many current fakebooks as BiaB arrangements, for sale at Norton Music website, with or without the accompanying fakebook. They are very accurately done, and one or more of them might cover your interests.
You will be surprised at how many tunes just don't exist in print. Learn to take those off your records or the radio. BiaB is a great help in that.