If you just want to find files with a certain name, use
The man page can be found HERE or by typing
man find at the terminal prompt.
Basically, find will recursively look for a file meeting criteria you specify. The easiest example:
find . -name file_name -print
That will search for a file named "file_name" starting in the current directory and searching below and print the files with that name.
find ~ -name ".DS_Store" -delete
That will find all the .DS_Store files and delete them.
You can search by name, regex, date. You can act on the file in any Unix way with the
You can also use find as the start of a more complex pipeline of actions. Example:
find . -type f -print | egrep -i '\.m4a$|\.mp3$'
Will find all the files with extensions .m4a or .mp3
find . -type f -print | egrep -i '\.m4a$|\.mp3$' | wc -l
Will give you a count of those files.