Ctpres,
I am glad to see you are doing it yourself. I dug my 40x80 pond with my 65hp 4WD Mahindra and backhoe.
http://www.tractorbynet.com/forums/projects/135413-i-finally-started-my-pond-28.html
I didn't dig my topsoil, but dozed it to the edge of the pond (my driveway), then just lifted it over the driveway. After putting in a dam keyway, I dozed clay out of the basin up on the dam to a depth of about 4 feet.
At that depth, I had to switch to the backhoe as it was a little narrow to turn hard in the basin with a 7 foot wide bucket full of clay. Done slowly, you can doze dirt or clay into the bucket, then haul it off. I did all this without a tooth bar at the start of the 2009 dry spell. After 4 feet, I just dug with the backhoe.
I also, dozed in standing water at a depth of 6 inches only one day. It was real muddy, but that was dozed out of the way quickly. I left a small underwater island like Meadowlarkponds mentioned. It was a fun project, but hauling the dirt, like others mentioned, was the time consumer. I had piled it up across the driveway and I am still trying to find the best place to put the clay spoils. I worked my Big
RED Beast hard in this project.
If you go swallow ends for ducks and such, let me know if you want some Mosquito fish to eat mosquito larvae. I got a source now that will give me all I want, as they breed fast.

hugs, Brandi