Cold air intakes and Ram airs

I was looking into performance mods for my 98 SR5. My dad recently sent the chip in to get it beefed up a little bit. Im just not satisfied with my pick up power while im driving on the street. Id like to have more get up and go. So I started looking into Ram Air's and Cold Air intakes. I know AEM is a good brand for the Intake and i looked at a reasonably priced one. Im just hesitant about installing one because i dont want to affect my gas mileage to severely. Anyone have an Intake or Ram air in there truck? If so what are you looking at as far as a drop in your mpg? Also have questions about lift types and heights. If anyone could direct me somewhere or has any suggestions. Im an aspiring Tacoma Modder and im a little new to all the jargen. Thanks guys