Use Spotlight. You can enter text into the Finder's search field without using wildcards. Or create more sophisticated searchs by using COMMAND-F to open the search window in the Finder. For example, to find all the jpegs on your drive (or in a folder) just enter ".jpg". Below is a way to use Spotlight to search for system files, but many other options are available from which to select.
Get Spotlight to search system files (and more)
- Enter the search term in the Finder window's search field.
- Click the [+] button in the search bar to add a search option.
- In the first drop down menu choose Other.
- Choose “System Files” from the list that pops up (and check the box to place in drop down menu to avoid this step later,) click on the OK button.
- Now back in the Finder choose Include from the second drop down menu.
However, if you want to perform command-line like searching you can use the Terminal in the Utilities folder. Download Man Viewer 3.2 for a complete access to the set of Terminal commands. Since OS X is a variant of Unix much of what is "under the hood" is Unix in origin.
An excellent third-party tool is EasyFind 4.9.1. It is a RegEx based tool so it accepts standard wildcards used in Unix.