Better Gas Mileage for my 05 Tahoe

Okay, I am sure there are a few people out there that can help me here. I have an 05 Tahoe and I am looking to improve my gas mileage a little bit. I also have 2 children and live on a modest income so I would like to get a few suggestions on how to do it cheap, lol. I am thinking a cold air intake would be a good way to start. Are there any suggestions out there somewhere?

Thanks

Better Mileage

I put a K&N intake kit, Flowmaster exhaust, and used a hypertech performance programmer and I am now getting very close to 20 MPG with my '05 Tahoe!

I understand a K & N cold air intake system is around $200 or so but what will the others run me? I am sure a flowmaster exhaust system is a little out of my budget. But i am interested in what one costs. I am sure in the long run it will be worth it no matter what it costs.

Thanks