Like the people above posted, The F-body pan is pretty popular. However I don't know if it will work with the stock framestands in the stock location and the Edelbrock plates. I don't believe that they push the engine back far enough. You would need to move the Frame stands back a little, but it would fit.
The CTS-V pan is the best choice in my honest opinion. It is a little deeper than the F-body pan. I can attest that it fits with the framestands in the stock location. It hangs down below the crossmember about an inch. With some small spacers under the frame stands it'll clear the tie rod ends.
The MAST pan looks killer, and probably the best fit for these cars. I don't think it's available yet, and from what I have read, it isn't a huge priority for MAST, so the final due date isn't clear. Cost isn't clear just yet either...
FYI, I agree with Chuck71. I found my CTS-V pan on LS1Tech.com for $130 shipped to my house. It was brand new (Off of a crate engine) and came with the pan, windage tray, gasket, pickup tube, and even filter (No I'm not going to use the filter)
but it was super clean for quite a bit less than other options.