Hi Ali7  The lock screen is Widget Locker, it's a paid app.  You can choose which sliders you want, and what you want on the sliders (the action that will occur).  When I slide the Internet one, it takes me to the Internet without unlocking the screen.  The thing I wasn't aware of with Widget Locker is that you can still activate your status/notificaton bar.  Anything that appears there you can get to while the screen is locked. I didn't need Tweetdeck as such, since any tweet that arrived shows in the status bar, but if I wanted to compose a Tweet without there already being something from Tweetdeck in the status bar then I'd need to have unlocked the screen to get to the app.  And it's that reason I chose to add some of the other apps to the lock screen, so I can have them there handy without unlocking the screen.

I user LauncherPro.  I've been able to customise what dock I use, and customise the icons for the 5 apps on the dock.  I've also got:
Countdown widget
3G (small widget)
Smooth Calendar widget
Digital Clock

All apps (for the widgets I've used) are free. 

I have the "donate" version of LauncherPro, but what you see on my homescreen you can do without the donate version.

The backgrounds are those that have been posted in this forum some time ago.  Sounds like Kiwijunglist might have them, or provided them.  There were links that took you to a secondary website where you could download them.