Attention everyone with AFTER MARKET PRODUCTS!

Now that I have your attention have a few questions and I hope you can help me out with.  I just put 22" rims on my blazers and notice they are very heavy compared to stock rims.  I was told to get more HP and better gas mileage I should put a air intake system and a new exhaust system on my 01 Blazer.  I went to a truck shope and they give me prices for both the intake and exhaust, but he also wanted to sale me a super chip!  Have anybody ever used a super chip and is it worth it?  Will it give you extra HP and gas mileage.  The intake system he wanted to put on was "AirAid" and "Gibson exhaust".  Are these both good products.  Do you or know anybody that used a "super chip", "AirAid Intake system", or "Gibson exhaust"?  What is the results?  What kind of performace should I expect by adding the AirAid intake system, Gibson exhaust, and a throttle body spacers?  I am very new to truck performace so what are some other good questions I should ask? 
 
Thanks in advance for helping me out,
 
 
Mr. Wet behind the ears