Upvote:2
Hilton and Sheraton are right in the airport. There are cheaper offsite locations very close by, but you will need to use their shuttle. For example for a midweek night next week, you'd pay around $130 for Sheraton or Hilton and offsite locations could be less than $80 (Ibis, Moxy, Park Inn Radisson)
If you go offsite, I would recommend contacting the hotel up front about shuttle instructions (pick up point, schedule, number to call, etc.). The airport is huge and fairly convoluted.
Stating the obvious: Typing "Frankfurt Airport Hotels" into Google will give a great overview of choices, prices and locations for any given date.
Upvote:4
There's a Hilton Garden Inn directly connected to the airport (FRA, let us know if you're going to HHN), which you could consider.
It's also a 12 minute trip by train from FRA to the city's main train station, which has connections all over the city, so you could use any hotel booking site to find a hotel in the city near public transit that meets your personal definition of "value for money." You could also give thought to where your land transit leaves from.