"I think it is the blower motor"
That's never actually a good foot to start off on. People who guess about parts often end up spending a lot more than if they had just taken it somewhere to begin with.
But...this one isn't rocket science. So first find out for sure whether it is the blower fan or not. Put your passenger's seat all the way back. Grab a flashlight, flip upside down and cram your head up under the glove box. Turn the fan on and make sure that's what the sound is. Now just have a look - you'll see what to do. Its probably one electrical plug and 3 small hex-head screws. You can also get a $20 repair manual at an auto parts store that would tell you how to do many things on your own.