The link is dead so for most Android phones I find them like this:

"Go to settings and turn on bluetooth. Click menu button and you will see the option Show received files . Alternatively every files sent via bluetooth will be stored in a folder named bluetooth in storage (if the files are not moved).Apr 17, 2014"
First hit with a google search https://www.google.com/search?q=where+are+android+bluetooth+received+files+stored