Go to your Google Adsense Account
Click on the My Ads Tab
Now click the link that says Search on the left pane
On the top click the tab that says New Custom Search Engine and fill in the fields as you wish.
Select Save and Get code and a iframe window will open, select the code, copy and than in the google blogpost where you want the code paste the code while you are in HTML mode when editing the post and your search bar will look like this.
Try mine out and enjoy!
Do you like how the eyeballs look on each side of my search bar pointing? Once you have selected an image that suites your needs, add an image and than anchor each image on the left and right. To get them to fit on one line you may have to edit your Google Custom Search Engine size. Once you have the images anchored, one on the left and the other on the right, just drag them to each side of the search bar.
To do this just change the character size from 55 characters to more or less, depending on your needs.