I suppose it's time for the scolding. Go to your distro repositories FIRST to install ANY package. In Ubuntu's case this would mean you get DEB packages, NOT TAR.GZ packages. No I am not sorry I shouted. I'm on Debian, which is so close to Ubuntu an Ubuntu chauvinist I know called his OS "Debian with Fancy eye candy" (even though it's more than that) and here is a PARTIAL list of what when I typed "apt-cache search ghc"
ghc6 - GHC - the Glasgow Haskell Compilation system
ghc6-doc - Documentation for the Glasgow Haskell Compilation system
ghc6-prof - Profiling libraries for the Glasgow Haskell Compilation system
gtk2-engines - theme engines for GTK+ 2.x
gtk2hs-doc - A GUI library for Haskell (Gtk2Hs) -- documentation and examples
haskell-filepath-doc - Transitional package
haskell-mode - A major mode for editing Haskell in Emacs
hmake - The Haskell Make System
hugs - A Haskell 98 interpreter
libghc6-alut-dev - Haskell ALUT binding for GHC
libghc6-alut-doc - Haskell ALUT binding for GHC; documentation
libghc6-alut-prof - Haskell ALUT binding for GHC; profiling libraries
libghc6-anydbm-dev - Generic DBM-type interface for Haskell, GHC package
libghc6-arrows-dev - Haskell arrow classes and transformers for GHC
libghc6-arrows-doc - Haskell arrow classes and transformers for GHC; documentation
libghc6-arrows-prof - Haskell arrow classes and transformers for GHC; profiling libraries
libghc6-binary-dev - Haskell library for binary serialisation using lazy ByteStrings
libghc6-binary-doc - Haskell library for binary serialisation; documentation
It is because of these dependency issues that we HAVE distros. So don't just throw the advantage away. (actually if you look in the directory you were in you will see packages to fix this, but it's better to go through the repositories).