Step1
Attend a game. This is pretty self-explanatory, and games are easy to find. Alaska and Vermont are the only two states that aren't home to at least one NCAA Division I football team. You might attend a Divsion II or III game regardless of whether or not there's a Division I school near you.
Step2
Use the Internet. Look at the list of links under Resources. On the web, you can find just about any information you will need about college football. You can also listen to and/or watch live games that may be unavailable on TV/radio in your area, or may not be televised at all.
Step3
Get a dish. Cable isn't horrible for college football, especially if you add a basic sports package that includes Comcast sports channels or Fox College Sports (Atlantic, Central, Pacific). It also helps if your cable company carries the Big Ten Network and the MTN (the Mountain).
As things stand right now though, I think the best bet in most areas is DirecTV WITH the SportsPack. With a basic DirecTV package, you get ESPN, ESPN2, the Big Ten Network, local channels such as ABC, NBC, CBS, and your local Fox Sports Net affiliate. Add the SportsPack for only $12/month and you get about three dozen additional sports channels, most of which carry college football. You get all markets of Fox Sports Network, not just your own local version, plus CSTV (College Sports Television), ESPNU, NESN, Versus, MASN, SNY, four different regions of Comcast Sports Net, and more.
For me, the low price and multiple channels make SportsPack a better deal than is ESPN's GamePlan, but the latter is an option too. With SportsPack you also can see college hockey and continue your subscription through spring for men's and women's hoops too instead of having to purchase ESPN FullCourt.