Design a Filter with Resonance
First, you need to start with in the s domain where a 2nd order transfer function (2 pole low pass filter) which can be written as follows.

H(s) = s^2 + 2zws + w^2

Lets start with omega = 1 and zeta = sqrt(2)/2, then

H(s) = s^2 + 1.414 s + 1 

This filter's response and pole locations are shown here.


To peak the response, simply modify zeta. Here zeta = 0.17 and omega = 1.

H(s) = s^2 + 0.34 s  + 1



Then to move the frequncy, change Omega. 
Here zeta = 0.17 and omega = 0.39

H(s) = s^2 + 0.1326s + 0.1521



Now all that is left is to determine the z domain coefficients. To do this, use the bilinear transform as shown here.



For the the last example I gave, use  A=1, B=0.136, C=0.1521, D=E=0, F=1, T=2 to calculate the a's and b's.

See this page for a derivation of the equations given here. Here is a rather simple tool that can generate any 2nd order response you want.