Tree I.D. Please

Hello, A few years back I was on the hunt for a tree that I could put in a neighbors front yard, at their request... They didn't have much to spend so I was on the look out for something cheep and found this tree at a local nursery, it was marked down to $20., wasn't tagged and I didn't bother to ask for the name. :\ The tree has grown into a beautiful specimen and all the neighbors love it, as a matter of fact on any hot day you will always find at least one conversation going on in its shade, and now others want one for their front yards. Can anyone here in this forum identify this beauty? The tree is 20 - 25ft tall, leaf is very furn like, has beautiful yellow flowers that are 1/2 inch or smaller, and has an umbrella shape. Thanks for your time and knowledge in advance :-)* here's the link to the photo http://thegardengeek.com/myalbum/5/91965/1651/0