Well only thing I could think of is get dialer@bar from the market, it puts a phone icon in the status bar so no matter what screen your on you can easily access the dialpad.. other then that, Im not sure..
I just installed Helix Launcher, and it has the phone icon on every screen. Gives you one touch access to the phone from any screen, and does not take up any real estate which would be the case if the whole dialpad was on a home screen. Even better in my opinion.