http://www.okstate.com/sports/m-footbl/s...14aae.html

It's pretty interesting. Some quotes that stick out:

Quote:In just the past two years, OSU's non-conference schedule has dropped from four opponents each year to three with the Big 12 Conference's decision to play nine league games annually instead of eight. As a result, Martin had to unload contracted non-conference matchups by cancelling games or by moving them to future dates.
"One of the series that was cancelled was a home-and-home with PURDUE," Martin said. "We tried multiple dates in multiple years, but the Big Ten was changing its league schedule as well. Both schools wanted to keep the contract, but we couldn't coordinate dates - even several years out."

Quote:But there are extenuating circumstances in Martin's case. He might be too nice. Several years ago, Oklahoma State was approached by fellow conference member TEXAS A&M, which needed a favor. The Aggies were about to sign a non-conference series with Arkansas to be played in AT&T Stadium in Arlington, but they needed OSU's help by moving a game, or two, or more.
In an effort to help out a fellow Big 12 member, OSU acquiesced and moved several games.

"I know we moved three to help them, and I think it may have affected two more games," Martin said.
As it turns out, Texas A&M left the Big 12 for the Southeastern Conference, and OSU got caught in a schedule squeeze for its troubles. Not only did OSU have to play at Texas two straight seasons, but the Cowboys had trouble filling an open date to start the 2012 season as an indirect result of the A&M-Arkansas series. After making contact with approximately 25 schools, OSU finally had a taker in SAVANNAH STATE.

Quote:As the facilities around Oklahoma State athletics have changed, so has the blueprint for football scheduling. During the years of Boone Pickens Stadium construction, OSU's home-field capacity shrunk to approximately 44,000.
With the loss of seating comes a drop in game-day revenue, which leads to smaller guarantees for the visitors. A guarantee is the amount of money a visiting team receives for making the trip and it is one of the tools used to balance a budget year. Quite simply, schools that pay smaller guarantees often have trouble attracting non-conference opponents who might be seeking a bigger check.

To help offset this particular scheduling dilemma, Martin began a 2-for-1 phase. Most teams outside of the "power conferences" have trouble landing marquee home opponents. OSU struck deals that resulted in smaller guarantees for opponents in exchange for a visit by OSU to their stadium -- the infamous 2-for-1. Oklahoma State played one game at TROY and Troy visited Stillwater twice, thus 2-for-1. As a result, OSU saved money with a smaller guarantee for the Trojans when they visited Stillwater, and Troy got the rare chance to host a Big 12 opponent.

There's more in there but it's just a glimpse into what AD's go through.