customization help bootsound, initial loading screen etc

basically im looking for the easiest way to customize everything i can in vanilla ubuntu version 12.06 i think it is(the latest official 12.whatever). The starting sound and how to enable it are the two at the top of my list, ive done the wallpaper, custom cursors would be nice, i would like to change the initial loading screen(i dont really like how its just bland purple)
also im a bit of a noob at this, as in just 5 minutes ago found out how to use the termanal, so im probably going to need the commands listed for anything using it, and thanks in advance

Take a look at the site below which explains changing the purple screen after the boot menu. I haven't used it myself so don't know how well it works:

Install Plymouth Manager and Change Boot Screen in Ubuntu/Linux Mint ~ Noobs on Ubuntu and Windows, HD Wallpapers, Tutorials

Ubuntu is using gnome desktop by default isn't it? There should be an application there that allows you to customise quite a lot of things.

As for the boot splash, you probably have to dig into the startup scripts to identify which file contains the image and go from there. I always inhibit the boot splash screen anyhow.

thanks for saying about gnome, i found and installed gnome tweak after some digging around online, ive also managed to install gnome shell extensions, but when i try and change the shell theme it wont allow me to do anything with the dropdown box and it says "could not find shell extensions". what would cause this, how do i fix it, and then how do i install a theme e.g the one here: hopskocz.deviantart@com/art/Applejack-Gnome-shell-3-2-theme-288622585
replacing the "@" with a "." in the link

Sorry Jof, can't be of much help with gnome. I first tried it about five years back. Didn't like it and now use only KDE.

Surely there is a kind of "Desktop Settings" and/or "System Settings" prog that you can use?

In KDE, there is a "Desktop Settings" that lets you set the look of the actual desktop and "System Settings" that allows you to set just about everything from desktop theme to which sound card to use for playing CDs.