follow my steps :
Step ( S ) 1 : Download GoldWave Editor Pro here : http://www.mediafire.com/?whj5udvwgluvcgo
S2 : Open GWEP and enter the key
S3 : You will see the red button " record " in the left of the screen , click on it
S4 : If the " New Sample " appear , change the " Sample Rate " to 44,100 and " Channels " to Stereo ( Dual )
S5 : After that , click to OK , and you will see the " Recording "
S6 : Find some tennis videos in YouTube , or another .
S7 : Click to " Record " in " Recording " and the GWEP will record any sounds in your computer ( about the microphone , i don't know )
S8 : When you want to stop recording , click to " Keep " and very huge frequency sound will appear in GWEP screen
S9 : Click in anywhere you want , and hower your mouse to the right , when you see the frequency sound blackened , you're doing right . To end this , release your mouse .
S10 : In the blackened frequency sound , click the right mouse , and click " Save Select Region As "
S11 : Change your file names .
S12 : Done
If you still don't understand , i will make a video