Hi there. If you can't find the Typo clock in the app market then you either have the Samsung Captivate or another Android device that doesn't allow for third party apps to be installed, as in AT&T's ridiculous policies. But fear not, there is a way to get it. I had a Samsung Captivate a couple of weeks ago and I had to root it just to be able to enjoy it to its fullest; and download apps like Typoclock.
Go to this website and see if you can get (you will need a QR Droid scanner or a similar app to scan the code): TypoClock is my new favorite Android clock widget | andrew | Androinica
. If you still can't still it then you will have to root your phone. The clock widget on my homescreen is "Simi Clock"
As for my lockscreen you have to have Launcher Pro first. Second you have to download the paid app Widget Locker. Then download an app called APK Manager. The process involves opening up the widgetlocker apk file, inserting a custom slider to replace one inside, signing the apk file, and then reinstalling it on your phone. I have posted this link which will best explain how to do it: [MOD][GUIDE] WidgetLocker Mods | Custom Lockscreens | Updated 21 Dec! - xda-developers
If these all sound too overwhelming don't give up hope!