what is your zipcode...so we may get a feel of your situation...distances, channels, etc.
what are you currently using for an antenna?
do you own satellite and is the ota diplexed...off air combined with satellite?
Do you split the signal...if so how may times...2 way, 3 way, etc.
The answers to the questions will help determine amplifier type (distribution amp or preamp) and gain (to help avoid overloading issues).